[PATCH v4 11/14] i2c-octeon: Rename driver to prepare for split
From: Jan Glauber
Date: Fri Mar 18 2016 - 04:50:13 EST
This is just an intermediate commit in preparation of
the driver split. The module rename in this commit
will be reverted in the next patch, this is just done
to make the series bisectible.
Signed-off-by: Jan Glauber <jglauber@xxxxxxxxxx>
---
drivers/i2c/busses/Makefile | 2 +-
drivers/i2c/busses/i2c-octeon-core.c | 1264 ++++++++++++++++++++++++++++++++++
drivers/i2c/busses/i2c-octeon.c | 1264 ----------------------------------
3 files changed, 1265 insertions(+), 1265 deletions(-)
create mode 100644 drivers/i2c/busses/i2c-octeon-core.c
delete mode 100644 drivers/i2c/busses/i2c-octeon.c
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 37f2819..3405286 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -91,7 +91,7 @@ obj-$(CONFIG_I2C_UNIPHIER) += i2c-uniphier.o
obj-$(CONFIG_I2C_UNIPHIER_F) += i2c-uniphier-f.o
obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o
obj-$(CONFIG_I2C_WMT) += i2c-wmt.o
-obj-$(CONFIG_I2C_OCTEON) += i2c-octeon.o
+obj-$(CONFIG_I2C_OCTEON) += i2c-octeon-core.o
obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o
obj-$(CONFIG_I2C_XLR) += i2c-xlr.o
obj-$(CONFIG_I2C_XLP9XX) += i2c-xlp9xx.o
diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c
new file mode 100644
index 0000000..444e8ed
--- /dev/null
+++ b/drivers/i2c/busses/i2c-octeon-core.c
@@ -0,0 +1,1264 @@
+/*
+ * (C) Copyright 2009-2010
+ * Nokia Siemens Networks, michael.lawnick.ext@xxxxxxx
+ *
+ * Portions Copyright (C) 2010 - 2016 Cavium, Inc.
+ *
+ * This is a driver for the i2c adapter in Cavium Networks' OCTEON processors.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/atomic.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/io.h>
+#include <linux/of.h>
+
+#include <asm/octeon/octeon.h>
+
+#define DRV_NAME "i2c-octeon"
+
+/* Register offsets */
+#define SW_TWSI 0x00
+#define TWSI_INT 0x10
+#define SW_TWSI_EXT 0x18
+
+/* Controller command patterns */
+#define SW_TWSI_V BIT_ULL(63) /* Valid bit */
+#define SW_TWSI_EIA BIT_ULL(61) /* Extended internal address */
+#define SW_TWSI_R BIT_ULL(56) /* Result or read bit */
+#define SW_TWSI_SOVR BIT_ULL(55) /* Size override */
+#define SW_TWSI_SIZE_SHIFT 52
+#define SW_TWSI_ADDR_SHIFT 40
+#define SW_TWSI_IA_SHIFT 32 /* Internal address */
+
+/* Controller opcode word (bits 60:57) */
+#define SW_TWSI_OP_SHIFT 57
+#define SW_TWSI_OP_7 (0ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_7_IA (1ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_10 (2ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_10_IA (3ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_TWSI_CLK (4ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_EOP (6ULL << SW_TWSI_OP_SHIFT) /* Extended opcode */
+
+/* Controller extended opcode word (bits 34:32) */
+#define SW_TWSI_EOP_SHIFT 32
+#define SW_TWSI_EOP_TWSI_DATA (SW_TWSI_OP_EOP | 1ULL << SW_TWSI_EOP_SHIFT)
+#define SW_TWSI_EOP_TWSI_CTL (SW_TWSI_OP_EOP | 2ULL << SW_TWSI_EOP_SHIFT)
+#define SW_TWSI_EOP_TWSI_CLKCTL (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
+#define SW_TWSI_EOP_TWSI_STAT (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
+#define SW_TWSI_EOP_TWSI_RST (SW_TWSI_OP_EOP | 7ULL << SW_TWSI_EOP_SHIFT)
+
+/* Controller command and status bits */
+#define TWSI_CTL_CE 0x80 /* High level controller enable */
+#define TWSI_CTL_ENAB 0x40 /* Bus enable */
+#define TWSI_CTL_STA 0x20 /* Master-mode start, HW clears when done */
+#define TWSI_CTL_STP 0x10 /* Master-mode stop, HW clears when done */
+#define TWSI_CTL_IFLG 0x08 /* HW event, SW writes 0 to ACK */
+#define TWSI_CTL_AAK 0x04 /* Assert ACK */
+
+/* Some status values */
+#define STAT_ERROR 0x00
+#define STAT_START 0x08
+#define STAT_RSTART 0x10
+#define STAT_TXADDR_ACK 0x18
+#define STAT_TXADDR_NAK 0x20
+#define STAT_TXDATA_ACK 0x28
+#define STAT_TXDATA_NAK 0x30
+#define STAT_LOST_ARB_38 0x38
+#define STAT_RXADDR_ACK 0x40
+#define STAT_RXADDR_NAK 0x48
+#define STAT_RXDATA_ACK 0x50
+#define STAT_RXDATA_NAK 0x58
+#define STAT_SLAVE_60 0x60
+#define STAT_LOST_ARB_68 0x68
+#define STAT_SLAVE_70 0x70
+#define STAT_LOST_ARB_78 0x78
+#define STAT_SLAVE_80 0x80
+#define STAT_SLAVE_88 0x88
+#define STAT_GENDATA_ACK 0x90
+#define STAT_GENDATA_NAK 0x98
+#define STAT_SLAVE_A0 0xA0
+#define STAT_SLAVE_A8 0xA8
+#define STAT_LOST_ARB_B0 0xB0
+#define STAT_SLAVE_LOST 0xB8
+#define STAT_SLAVE_NAK 0xC0
+#define STAT_SLAVE_ACK 0xC8
+#define STAT_AD2W_ACK 0xD0
+#define STAT_AD2W_NAK 0xD8
+#define STAT_IDLE 0xF8
+
+/* TWSI_INT values */
+#define TWSI_INT_ST_INT BIT_ULL(0)
+#define TWSI_INT_TS_INT BIT_ULL(1)
+#define TWSI_INT_CORE_INT BIT_ULL(2)
+#define TWSI_INT_ST_EN BIT_ULL(4)
+#define TWSI_INT_TS_EN BIT_ULL(5)
+#define TWSI_INT_CORE_EN BIT_ULL(6)
+#define TWSI_INT_SDA_OVR BIT_ULL(8)
+#define TWSI_INT_SCL_OVR BIT_ULL(9)
+#define TWSI_INT_SDA BIT_ULL(10)
+#define TWSI_INT_SCL BIT_ULL(11)
+
+struct octeon_i2c {
+ wait_queue_head_t queue;
+ struct i2c_adapter adap;
+ int irq;
+ int hlc_irq; /* For cn7890 only */
+ u32 twsi_freq;
+ int sys_freq;
+ void __iomem *twsi_base;
+ struct device *dev;
+ bool hlc_enabled;
+ bool broken_irq_mode;
+ bool broken_irq_check;
+ void (*int_en)(struct octeon_i2c *);
+ void (*int_dis)(struct octeon_i2c *);
+ void (*hlc_int_en)(struct octeon_i2c *);
+ void (*hlc_int_dis)(struct octeon_i2c *);
+ atomic_t int_en_cnt;
+ atomic_t hlc_int_en_cnt;
+};
+
+static int reset_how;
+
+static void writeqflush(u64 val, void __iomem *addr)
+{
+ __raw_writeq(val, addr);
+ __raw_readq(addr); /* wait for write to land */
+}
+
+/**
+ * octeon_i2c_write_sw - write an I2C core register
+ * @i2c: The struct octeon_i2c
+ * @eop_reg: Register selector
+ * @data: Value to be written
+ *
+ * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
+ */
+static void octeon_i2c_write_sw(struct octeon_i2c *i2c, u64 eop_reg, u32 data)
+{
+ u64 tmp;
+
+ __raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + SW_TWSI);
+ do {
+ tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
+ } while ((tmp & SW_TWSI_V) != 0);
+}
+
+/**
+ * octeon_i2c_read_sw64 - read an I2C core register
+ * @i2c: The struct octeon_i2c
+ * @eop_reg: Register selector
+ *
+ * Returns the data.
+ *
+ * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
+ */
+static u64 octeon_i2c_read_sw64(struct octeon_i2c *i2c, u64 eop_reg)
+{
+ u64 tmp;
+
+ __raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base + SW_TWSI);
+ do {
+ tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
+ } while ((tmp & SW_TWSI_V) != 0);
+
+ return tmp;
+}
+
+/**
+ * octeon_i2c_read_sw - read lower bits of an I2C core register
+ * @i2c: The struct octeon_i2c
+ * @eop_reg: Register selector
+ *
+ * Returns the data.
+ *
+ * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
+ */
+static u8 octeon_i2c_read_sw(struct octeon_i2c *i2c, u64 eop_reg)
+{
+ return octeon_i2c_read_sw64(i2c, eop_reg) & 0xFF;
+}
+
+/**
+ * octeon_i2c_write_int - write the TWSI_INT register
+ * @i2c: The struct octeon_i2c
+ * @data: Value to be written
+ */
+static void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
+{
+ writeqflush(data, i2c->twsi_base + TWSI_INT);
+}
+
+/**
+ * octeon_i2c_int_enable - enable the CORE interrupt
+ * @i2c: The struct octeon_i2c
+ *
+ * The interrupt will be asserted when there is non-STAT_IDLE state in
+ * the SW_TWSI_EOP_TWSI_STAT register.
+ */
+static void octeon_i2c_int_enable(struct octeon_i2c *i2c)
+{
+ octeon_i2c_write_int(i2c, TWSI_INT_CORE_EN);
+}
+
+/* disable the CORE interrupt */
+static void octeon_i2c_int_disable(struct octeon_i2c *i2c)
+{
+ /* clear TS/ST/IFLG events */
+ octeon_i2c_write_int(i2c, 0);
+}
+
+static void octeon_i2c_disable_hlc(struct octeon_i2c *i2c)
+{
+ if (!i2c->hlc_enabled)
+ return;
+
+ i2c->hlc_enabled = false;
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+}
+
+/**
+ * octeon_i2c_int_enable78 - enable the CORE interrupt
+ * @i2c: The struct octeon_i2c
+ *
+ * The interrupt will be asserted when there is non-STAT_IDLE state in the
+ * SW_TWSI_EOP_TWSI_STAT register.
+ */
+static void octeon_i2c_int_enable78(struct octeon_i2c *i2c)
+{
+ atomic_inc_return(&i2c->int_en_cnt);
+ enable_irq(i2c->irq);
+}
+
+static void __octeon_i2c_irq_disable(atomic_t *cnt, int irq)
+{
+ int count;
+
+ /*
+ * The interrupt can be disabled in two places, but we only
+ * want to make the disable_irq_nosync() call once, so keep
+ * track with the atomic variable.
+ */
+ count = atomic_dec_if_positive(cnt);
+ if (count >= 0)
+ disable_irq_nosync(irq);
+}
+
+/* disable the CORE interrupt */
+static void octeon_i2c_int_disable78(struct octeon_i2c *i2c)
+{
+ __octeon_i2c_irq_disable(&i2c->int_en_cnt, i2c->irq);
+}
+
+/**
+ * octeon_i2c_hlc_int_enable78 - enable the ST interrupt
+ * @i2c: The struct octeon_i2c
+ *
+ * The interrupt will be asserted when there is non-STAT_IDLE state in
+ * the SW_TWSI_EOP_TWSI_STAT register.
+ */
+static void octeon_i2c_hlc_int_enable78(struct octeon_i2c *i2c)
+{
+ atomic_inc_return(&i2c->hlc_int_en_cnt);
+ enable_irq(i2c->hlc_irq);
+}
+
+/* disable the ST interrupt */
+static void octeon_i2c_hlc_int_disable78(struct octeon_i2c *i2c)
+{
+ __octeon_i2c_irq_disable(&i2c->hlc_int_en_cnt, i2c->hlc_irq);
+}
+
+/**
+ * octeon_i2c_unblock - unblock the bus
+ * @i2c: The struct octeon_i2c
+ *
+ * If there was a reset while a device was driving 0 to bus, bus is blocked.
+ * We toggle it free manually by some clock cycles and send a stop.
+ */
+static void octeon_i2c_unblock(struct octeon_i2c *i2c)
+{
+ int state, i;
+
+ octeon_i2c_disable_hlc(i2c);
+ dev_dbg(i2c->dev, "%s\n", __func__);
+
+ /* cycle 8+1 clocks with SDA high */
+ for (i = 0; i < 9; i++) {
+ octeon_i2c_write_int(i2c, 0);
+ udelay(5);
+ state = __raw_readq(i2c->twsi_base + TWSI_INT);
+ if (state & (TWSI_INT_SDA | TWSI_INT_SCL))
+ break;
+ octeon_i2c_write_int(i2c, TWSI_INT_SCL_OVR);
+ udelay(5);
+ }
+ /* hand-crank a STOP */
+ octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR | TWSI_INT_SCL_OVR);
+ udelay(5);
+ octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR);
+ udelay(5);
+ octeon_i2c_write_int(i2c, 0);
+}
+
+/* interrupt service routine */
+static irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
+{
+ struct octeon_i2c *i2c = dev_id;
+
+ i2c->int_dis(i2c);
+ wake_up(&i2c->queue);
+
+ return IRQ_HANDLED;
+}
+
+/* HLC interrupt service routine */
+static irqreturn_t octeon_i2c_hlc_isr78(int irq, void *dev_id)
+{
+ struct octeon_i2c *i2c = dev_id;
+
+ i2c->hlc_int_dis(i2c);
+ wake_up(&i2c->queue);
+
+ return IRQ_HANDLED;
+}
+
+static u64 octeon_i2c_read_ctl(struct octeon_i2c *i2c)
+{
+ return octeon_i2c_read_sw64(i2c, SW_TWSI_EOP_TWSI_CTL);
+}
+
+static int octeon_i2c_test_iflg(struct octeon_i2c *i2c)
+{
+ return (octeon_i2c_read_ctl(i2c) & TWSI_CTL_IFLG) != 0;
+}
+
+#define I2C_OCTEON_IFLG_WAIT 80 /* microseconds */
+
+/*
+ * Wait-helper which addresses the delayed-IFLAG problem by re-polling for
+ * missing TWSI_CTL[IFLG] a few us later, when irq has signalled an event,
+ * but none found. Skip this re-poll on the first (non-wakeup) call.
+ */
+static int poll_iflg(struct octeon_i2c *i2c, int *first_p)
+{
+ int iflg = octeon_i2c_test_iflg(i2c);
+
+ if (iflg)
+ return 1;
+ if (*first_p)
+ *first_p = 0;
+ else {
+ usleep_range(I2C_OCTEON_IFLG_WAIT, 2 * I2C_OCTEON_IFLG_WAIT);
+ iflg = octeon_i2c_test_iflg(i2c);
+ }
+ return iflg;
+}
+
+/**
+ * octeon_i2c_wait - wait for the IFLG to be set
+ * @i2c: The struct octeon_i2c
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_wait(struct octeon_i2c *i2c)
+{
+ long time_left;
+ int first = 1;
+
+ if (i2c->broken_irq_mode) {
+ /*
+ * Some chip revisions seem to not assert the irq in
+ * the interrupt controller. So we must poll for the
+ * IFLG change.
+ */
+ u64 end = get_jiffies_64() + i2c->adap.timeout;
+
+ while (!octeon_i2c_test_iflg(i2c) &&
+ time_before64(get_jiffies_64(), end))
+ udelay(50);
+
+ return octeon_i2c_test_iflg(i2c) ? 0 : -ETIMEDOUT;
+ }
+
+ i2c->int_en(i2c);
+ time_left = wait_event_timeout(i2c->queue, poll_iflg(i2c, &first),
+ i2c->adap.timeout);
+ i2c->int_dis(i2c);
+
+ if (time_left <= 0 && i2c->broken_irq_check &&
+ octeon_i2c_test_iflg(i2c)) {
+ dev_err(i2c->dev,
+ "broken irq connection detected, switching to polling mode.\n");
+ i2c->broken_irq_mode = true;
+ return 0;
+ }
+ if (!time_left) {
+ dev_dbg(i2c->dev, "%s: timeout\n", __func__);
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+/*
+ * Cleanup low-level state & enable high-level.
+ * Returns -EAGAIN if low-level state could not be cleaned.
+ */
+static int octeon_i2c_enable_hlc(struct octeon_i2c *i2c)
+{
+ int try = 0, ret = 0;
+ u64 val;
+
+ if (i2c->hlc_enabled)
+ return 0;
+ i2c->hlc_enabled = true;
+
+ while (1) {
+ val = octeon_i2c_read_ctl(i2c) & (TWSI_CTL_STA | TWSI_CTL_STP);
+ if (!val)
+ break;
+
+ /* clear IFLG event */
+ if (val & TWSI_CTL_IFLG)
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+
+ if (try++ > 100) {
+ pr_err("%s: giving up\n", __func__);
+ ret = -EAGAIN;
+ break;
+ }
+
+ /* spin until any start/stop has finished */
+ udelay(10);
+ }
+
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
+ TWSI_CTL_CE | TWSI_CTL_AAK | TWSI_CTL_ENAB);
+ return ret;
+}
+
+static int octeon_i2c_lost_arb(u8 code, int final_read)
+{
+ switch (code) {
+ /* Arbitration lost */
+ case STAT_LOST_ARB_38:
+ case STAT_LOST_ARB_68:
+ case STAT_LOST_ARB_78:
+ case STAT_LOST_ARB_B0:
+ return -EAGAIN;
+
+ /* Being addressed as slave, should back off & listen */
+ case STAT_SLAVE_60:
+ case STAT_SLAVE_70:
+ case STAT_GENDATA_ACK:
+ case STAT_GENDATA_NAK:
+ return -EIO;
+
+ /* Core busy as slave */
+ case STAT_SLAVE_80:
+ case STAT_SLAVE_88:
+ case STAT_SLAVE_A0:
+ case STAT_SLAVE_A8:
+ case STAT_SLAVE_LOST:
+ case STAT_SLAVE_NAK:
+ case STAT_SLAVE_ACK:
+ return -EIO;
+
+ /* ACK allowed on pre-terminal bytes only */
+ case STAT_RXDATA_ACK:
+ if (!final_read)
+ return 0;
+ return -EAGAIN;
+
+ /* NAK allowed on terminal byte only */
+ case STAT_RXDATA_NAK:
+ if (final_read)
+ return 0;
+ return -EAGAIN;
+ case STAT_TXDATA_NAK:
+ case STAT_TXADDR_NAK:
+ case STAT_RXADDR_NAK:
+ case STAT_AD2W_NAK:
+ return -EAGAIN;
+ }
+ return 0;
+}
+
+static int check_arb(struct octeon_i2c *i2c, int final_read)
+{
+ return octeon_i2c_lost_arb(octeon_i2c_read_sw(i2c,
+ SW_TWSI_EOP_TWSI_STAT), final_read);
+}
+
+/* send STOP to the bus */
+static void octeon_i2c_stop(struct octeon_i2c *i2c)
+{
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
+ TWSI_CTL_ENAB | TWSI_CTL_STP);
+}
+
+static bool octeon_i2c_hlc_test_ready(struct octeon_i2c *i2c)
+{
+ u64 val = __raw_readq(i2c->twsi_base + SW_TWSI);
+
+ return (val & SW_TWSI_V) == 0;
+}
+
+static void octeon_i2c_hlc_int_enable(struct octeon_i2c *i2c)
+{
+ octeon_i2c_write_int(i2c, TWSI_INT_ST_EN);
+}
+
+static void octeon_i2c_hlc_int_clear(struct octeon_i2c *i2c)
+{
+ /* clear ST/TS events, listen for neither */
+ octeon_i2c_write_int(i2c, TWSI_INT_ST_INT | TWSI_INT_TS_INT);
+}
+
+/**
+ * octeon_i2c_hlc_wait - wait for an HLC operation to complete
+ * @i2c: The struct octeon_i2c
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
+{
+ int time_left;
+
+ if (i2c->broken_irq_mode) {
+ /*
+ * Some cn38xx boards did not assert the irq in
+ * the interrupt controller. So we must poll for the
+ * IFLG change.
+ */
+ u64 end = get_jiffies_64() + i2c->adap.timeout;
+
+ while (!octeon_i2c_hlc_test_ready(i2c) &&
+ time_before64(get_jiffies_64(), end))
+ udelay(50);
+
+ return octeon_i2c_hlc_test_ready(i2c) ? 0 : -ETIMEDOUT;
+ }
+
+ i2c->hlc_int_en(i2c);
+ time_left = wait_event_interruptible_timeout(i2c->queue,
+ octeon_i2c_hlc_test_ready(i2c),
+ i2c->adap.timeout);
+ i2c->hlc_int_dis(i2c);
+ if (!time_left)
+ octeon_i2c_hlc_int_clear(i2c);
+
+ if (time_left <= 0 && i2c->broken_irq_check &&
+ octeon_i2c_hlc_test_ready(i2c)) {
+ dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n");
+ i2c->broken_irq_mode = true;
+ return 0;
+ }
+
+ if (!time_left) {
+ dev_dbg(i2c->dev, "%s: timeout\n", __func__);
+ return -ETIMEDOUT;
+ }
+ if (time_left < 0) {
+ dev_dbg(i2c->dev, "%s: wait interrupted\n", __func__);
+ return time_left;
+ }
+ return 0;
+}
+
+/* high-level-controller pure read of up to 8 bytes */
+static int octeon_i2c_simple_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+ int i, j, ret = 0;
+ u64 cmd;
+
+ octeon_i2c_enable_hlc(i2c);
+ cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
+ /* SIZE */
+ cmd |= (u64) (msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
+ /* A */
+ cmd |= (u64) (msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
+
+ if (msgs[0].flags & I2C_M_TEN)
+ cmd |= SW_TWSI_OP_10;
+ else
+ cmd |= SW_TWSI_OP_7;
+
+ octeon_i2c_hlc_int_clear(i2c);
+ __raw_writeq(cmd, i2c->twsi_base + SW_TWSI);
+
+ ret = octeon_i2c_hlc_wait(i2c);
+ if (ret)
+ goto err;
+
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
+ if ((cmd & SW_TWSI_R) == 0)
+ return -EAGAIN;
+
+ for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
+ msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
+
+ if (msgs[0].len > 4) {
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
+ for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
+ msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
+ }
+
+err:
+ return ret;
+}
+
+/* high-level-controller pure write of up to 8 bytes */
+static int octeon_i2c_simple_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+ int i, j, ret = 0;
+ u64 cmd;
+
+ octeon_i2c_enable_hlc(i2c);
+ octeon_i2c_hlc_int_clear(i2c);
+
+ ret = check_arb(i2c, false);
+ if (ret)
+ goto err;
+
+ cmd = SW_TWSI_V | SW_TWSI_SOVR;
+ /* SIZE */
+ cmd |= (u64) (msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
+ /* A */
+ cmd |= (u64) (msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
+
+ if (msgs[0].flags & I2C_M_TEN)
+ cmd |= SW_TWSI_OP_10;
+ else
+ cmd |= SW_TWSI_OP_7;
+
+ for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
+ cmd |= (u64)msgs[0].buf[j] << (8 * i);
+
+ if (msgs[0].len > 4) {
+ u64 ext = 0;
+
+ for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
+ ext |= (u64) msgs[0].buf[j] << (8 * i);
+ writeqflush(ext, i2c->twsi_base + SW_TWSI_EXT);
+ }
+
+ writeqflush(cmd, i2c->twsi_base + SW_TWSI);
+
+ ret = octeon_i2c_hlc_wait(i2c);
+ if (ret)
+ goto err;
+
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
+ if ((cmd & SW_TWSI_R) == 0)
+ return -EAGAIN;
+
+ ret = check_arb(i2c, false);
+
+err:
+ return ret;
+}
+
+/* high-level-controller composite write+read, msg0=addr, msg1=data */
+static int octeon_i2c_ia_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+ int i, j, ret = 0;
+ u64 cmd;
+
+ octeon_i2c_enable_hlc(i2c);
+
+ cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
+ /* SIZE */
+ cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
+ /* A */
+ cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
+
+ if (msgs[0].flags & I2C_M_TEN)
+ cmd |= SW_TWSI_OP_10_IA;
+ else
+ cmd |= SW_TWSI_OP_7_IA;
+
+ if (msgs[0].len == 2) {
+ u64 ext = 0;
+
+ cmd |= SW_TWSI_EIA;
+ ext = (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+ cmd |= (u64) msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
+ __raw_writeq(ext, i2c->twsi_base + SW_TWSI_EXT);
+ } else
+ cmd |= (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+
+ octeon_i2c_hlc_int_clear(i2c);
+ writeqflush(cmd, i2c->twsi_base + SW_TWSI);
+
+ ret = octeon_i2c_hlc_wait(i2c);
+ if (ret)
+ goto err;
+
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
+ if ((cmd & SW_TWSI_R) == 0)
+ return -EAGAIN;
+
+ for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
+ msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
+
+ if (msgs[1].len > 4) {
+ cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
+ for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
+ msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
+ }
+
+err:
+ return ret;
+}
+
+/* high-level-controller composite write+write, m[0]len<=2, m[1]len<=8 */
+static int octeon_i2c_ia_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+ bool set_ext = false;
+ int i, j, ret = 0;
+ u64 cmd, ext = 0;
+
+ octeon_i2c_enable_hlc(i2c);
+
+ cmd = SW_TWSI_V | SW_TWSI_SOVR;
+ /* SIZE */
+ cmd |= (u64) (msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
+ /* A */
+ cmd |= (u64) (msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
+
+ if (msgs[0].flags & I2C_M_TEN)
+ cmd |= SW_TWSI_OP_10_IA;
+ else
+ cmd |= SW_TWSI_OP_7_IA;
+
+ if (msgs[0].len == 2) {
+ cmd |= SW_TWSI_EIA;
+ ext |= (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+ set_ext = true;
+ cmd |= (u64) msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
+ } else
+ cmd |= (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+
+ for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
+ cmd |= (u64) msgs[1].buf[j] << (8 * i);
+
+ if (msgs[1].len > 4) {
+ for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
+ ext |= (u64)msgs[1].buf[j] << (8 * i);
+ set_ext = true;
+ }
+ if (set_ext)
+ writeqflush(ext, i2c->twsi_base + SW_TWSI_EXT);
+
+ octeon_i2c_hlc_int_clear(i2c);
+ writeqflush(cmd, i2c->twsi_base + SW_TWSI);
+
+ ret = octeon_i2c_hlc_wait(i2c);
+ if (ret)
+ goto err;
+
+ cmd = octeon_i2c_read_sw64(i2c, SW_TWSI_EOP_TWSI_STAT);
+ if ((cmd & SW_TWSI_R) == 0)
+ return -EAGAIN;
+ ret = octeon_i2c_lost_arb(cmd, false);
+
+err:
+ return ret;
+}
+
+/* calculate and set clock divisors */
+static void octeon_i2c_set_clock(struct octeon_i2c *i2c)
+{
+ int tclk, thp_base, inc, thp_idx, mdiv_idx, ndiv_idx, foscl, diff;
+ int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = 1000000;
+
+ for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
+ /*
+ * An mdiv value of less than 2 seems to not work well
+ * with ds1337 RTCs, so we constrain it to larger values.
+ */
+ for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
+ /*
+ * For given ndiv and mdiv values check the
+ * two closest thp values.
+ */
+ tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
+ tclk *= (1 << ndiv_idx);
+ thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
+
+ for (inc = 0; inc <= 1; inc++) {
+ thp_idx = thp_base + inc;
+ if (thp_idx < 5 || thp_idx > 0xff)
+ continue;
+
+ foscl = i2c->sys_freq / (2 * (thp_idx + 1));
+ foscl = foscl / (1 << ndiv_idx);
+ foscl = foscl / (mdiv_idx + 1) / 10;
+ diff = abs(foscl - i2c->twsi_freq);
+ if (diff < delta_hz) {
+ delta_hz = diff;
+ thp = thp_idx;
+ mdiv = mdiv_idx;
+ ndiv = ndiv_idx;
+ }
+ }
+ }
+ }
+ octeon_i2c_write_sw(i2c, SW_TWSI_OP_TWSI_CLK, thp);
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
+}
+
+static int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c)
+{
+ u8 status = 0;
+ int tries;
+
+ /* reset controller */
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_RST, 0);
+
+ for (tries = 10; tries && status != STAT_IDLE; tries--) {
+ udelay(1);
+ status = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
+ }
+
+ if (status != STAT_IDLE) {
+ dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n",
+ __func__, status);
+ return -EIO;
+ }
+
+ /* toggle twice to force both teardowns */
+ octeon_i2c_enable_hlc(i2c);
+ octeon_i2c_disable_hlc(i2c);
+ return 0;
+}
+
+/*
+ * TWSI state seems stuck. Not sure if it's TWSI-engine state or something
+ * else on bus. The initial _stop() is always harmless, it just resets state
+ * machine, does not _transmit_ STOP unless engine was active.
+ */
+static int start_unstick(struct octeon_i2c *i2c)
+{
+ octeon_i2c_stop(i2c);
+
+ /*
+ * Response is escalated over successive calls,
+ * as EAGAIN provokes retries from i2c/core.
+ */
+ switch (reset_how++ % 4) {
+ case 0:
+ /* just the stop above */
+ break;
+ case 1:
+ /*
+ * Controller refused to send start flag. May be a
+ * client is holding SDA low? Let's try to free it.
+ */
+ octeon_i2c_unblock(i2c);
+ break;
+ case 2:
+ /* re-init our TWSI hardware */
+ octeon_i2c_init_lowlevel(i2c);
+ break;
+ default:
+ /* retry in caller */
+ reset_how = 0;
+ return -EAGAIN;
+ }
+ return 0;
+}
+
+/**
+ * octeon_i2c_start - send START to the bus
+ * @i2c: The struct octeon_i2c
+ * @first: first msg in combined operation?
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_start(struct octeon_i2c *i2c, int first)
+{
+ int result;
+ u8 data;
+
+ octeon_i2c_disable_hlc(i2c);
+
+ while (1) {
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
+ TWSI_CTL_ENAB | TWSI_CTL_STA);
+
+ result = octeon_i2c_wait(i2c);
+ data = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
+
+ switch (data) {
+ case STAT_START:
+ case STAT_RSTART:
+ if (!first)
+ return -EAGAIN;
+ reset_how = 0;
+ return 0;
+ case STAT_RXADDR_ACK:
+ if (first)
+ return -EAGAIN;
+ return start_unstick(i2c);
+ /*
+ * case STAT_IDLE:
+ * case STAT_ERROR:
+ */
+ default:
+ if (!first)
+ return -EAGAIN;
+ start_unstick(i2c);
+ }
+ }
+ return 0;
+}
+
+/**
+ * octeon_i2c_read - receive data from the bus via low-level controller
+ * @i2c: The struct octeon_i2c
+ * @target: Target address
+ * @data: Pointer to the location to store the data
+ * @rlength: Length of the data
+ * @phase: which phase of a combined operation.
+ * @recv_len: flag for length byte
+ *
+ * The address is sent over the bus, then the data is read.
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_read(struct octeon_i2c *i2c, int target, u8 *data,
+ u16 *rlength, bool first, bool last, bool recv_len)
+{
+ u8 ctl = TWSI_CTL_ENAB | TWSI_CTL_AAK;
+ int i, result, length = *rlength;
+ u8 tmp;
+
+ if (length < 1)
+ return -EINVAL;
+
+ result = octeon_i2c_start(i2c, first);
+ if (result)
+ return result;
+
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, (target << 1) | 1);
+
+ for (i = 0; i < length; ) {
+ tmp = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
+ result = octeon_i2c_lost_arb(tmp, !(ctl & TWSI_CTL_AAK));
+ if (result)
+ return result;
+
+ switch (tmp) {
+ case STAT_RXDATA_ACK:
+ case STAT_RXDATA_NAK:
+ data[i++] = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_DATA);
+ }
+
+
+ /* NAK last recv'd byte, as a no-more-please */
+ if (last && i == length - 1)
+ ctl &= ~TWSI_CTL_AAK;
+
+ /* clr iflg to allow next event */
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, ctl);
+ result = octeon_i2c_wait(i2c);
+ if (result)
+ return result;
+ if (recv_len && i == 0) {
+ if (data[i] > I2C_SMBUS_BLOCK_MAX + 1) {
+ dev_err(i2c->dev,
+ "%s: read len > I2C_SMBUS_BLOCK_MAX %d\n",
+ __func__, data[i]);
+ return -EPROTO;
+ }
+ length += data[i];
+ }
+ }
+ *rlength = length;
+ return 0;
+}
+
+/**
+ * octeon_i2c_write - send data to the bus via low-level controller
+ * @i2c: The struct octeon_i2c
+ * @target: Target address
+ * @data: Pointer to the data to be sent
+ * @length: Length of the data
+ * @last: is last msg in combined operation?
+ *
+ * The address is sent over the bus, then the data.
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_write(struct octeon_i2c *i2c, int target,
+ const u8 *data, int length, int first, int last)
+{
+ int i, result;
+
+ result = octeon_i2c_start(i2c, first);
+ if (result)
+ return result;
+
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, target << 1);
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+
+ result = octeon_i2c_wait(i2c);
+ if (result)
+ return result;
+
+ for (i = 0; i < length; i++) {
+ result = check_arb(i2c, false);
+ if (result)
+ return result;
+
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, data[i]);
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+
+ result = octeon_i2c_wait(i2c);
+ if (result)
+ return result;
+ result = check_arb(i2c, false);
+ if (result)
+ return result;
+ }
+
+ return 0;
+}
+
+/**
+ * octeon_i2c_xfer - The driver's master_xfer function
+ * @adap: Pointer to the i2c_adapter structure
+ * @msgs: Pointer to the messages to be processed
+ * @num: Length of the MSGS array
+ *
+ * Returns the number of messages processed, or a negative errno on failure.
+ */
+static int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
+ int num)
+{
+ struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+ int i, ret = 0;
+
+ if (num == 1) {
+ if (msgs[0].len > 0 && msgs[0].len <= 8) {
+ if (msgs[0].flags & I2C_M_RD)
+ ret = octeon_i2c_simple_read(i2c, msgs);
+ else
+ ret = octeon_i2c_simple_write(i2c, msgs);
+ goto out;
+ }
+ } else if (num == 2) {
+ if ((msgs[0].flags & I2C_M_RD) == 0 &&
+ (msgs[1].flags & I2C_M_RECV_LEN) == 0 &&
+ msgs[0].len > 0 && msgs[0].len <= 2 &&
+ msgs[1].len > 0 && msgs[1].len <= 8 &&
+ msgs[0].addr == msgs[1].addr) {
+ if (msgs[1].flags & I2C_M_RD)
+ ret = octeon_i2c_ia_read(i2c, msgs);
+ else
+ ret = octeon_i2c_ia_write(i2c, msgs);
+ goto out;
+ }
+ }
+
+ for (i = 0; ret == 0 && i < num; i++) {
+ struct i2c_msg *pmsg = &msgs[i];
+ bool last = (i == (num - 1));
+
+ dev_dbg(i2c->dev,
+ "Doing %s %d byte(s) to/from 0x%02x - %d of %d messages\n",
+ pmsg->flags & I2C_M_RD ? "read" : "write",
+ pmsg->len, pmsg->addr, i + 1, num);
+ if (pmsg->flags & I2C_M_RD)
+ ret = octeon_i2c_read(i2c, pmsg->addr, pmsg->buf,
+ &pmsg->len, !i, last,
+ pmsg->flags & I2C_M_RECV_LEN);
+ else
+ ret = octeon_i2c_write(i2c, pmsg->addr, pmsg->buf,
+ pmsg->len, !i, last);
+ }
+ octeon_i2c_stop(i2c);
+out:
+ return (ret != 0) ? ret : num;
+}
+
+static u32 octeon_i2c_functionality(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
+ I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_SMBUS_BLOCK_PROC_CALL;
+}
+
+static const struct i2c_algorithm octeon_i2c_algo = {
+ .master_xfer = octeon_i2c_xfer,
+ .functionality = octeon_i2c_functionality,
+};
+
+static struct i2c_adapter octeon_i2c_ops = {
+ .owner = THIS_MODULE,
+ .name = "OCTEON adapter",
+ .algo = &octeon_i2c_algo,
+};
+
+static int octeon_i2c_probe(struct platform_device *pdev)
+{
+ struct device_node *node = pdev->dev.of_node;
+ int irq, result = 0, hlc_irq = 0;
+ struct resource *res_mem;
+ struct octeon_i2c *i2c;
+ bool cn78xx_style;
+
+ cn78xx_style = of_device_is_compatible(node, "cavium,octeon-7890-twsi");
+ if (cn78xx_style) {
+ hlc_irq = platform_get_irq(pdev, 0);
+ if (hlc_irq < 0)
+ return hlc_irq;
+
+ irq = platform_get_irq(pdev, 2);
+ if (irq < 0)
+ return irq;
+ } else {
+ /* All adaptors have an irq. */
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+ }
+
+ i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
+ if (!i2c) {
+ result = -ENOMEM;
+ goto out;
+ }
+ i2c->dev = &pdev->dev;
+
+ res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ i2c->twsi_base = devm_ioremap_resource(&pdev->dev, res_mem);
+ if (IS_ERR(i2c->twsi_base)) {
+ result = PTR_ERR(i2c->twsi_base);
+ goto out;
+ }
+
+ /*
+ * "clock-rate" is a legacy binding, the official binding is
+ * "clock-frequency". Try the official one first and then
+ * fall back if it doesn't exist.
+ */
+ if (of_property_read_u32(node, "clock-frequency", &i2c->twsi_freq) &&
+ of_property_read_u32(node, "clock-rate", &i2c->twsi_freq)) {
+ dev_err(i2c->dev,
+ "no I2C 'clock-rate' or 'clock-frequency' property\n");
+ result = -ENXIO;
+ goto out;
+ }
+
+ i2c->sys_freq = octeon_get_io_clock_rate();
+
+ init_waitqueue_head(&i2c->queue);
+
+ i2c->irq = irq;
+
+ if (cn78xx_style) {
+ i2c->hlc_irq = hlc_irq;
+
+ i2c->int_en = octeon_i2c_int_enable78;
+ i2c->int_dis = octeon_i2c_int_disable78;
+ i2c->hlc_int_en = octeon_i2c_hlc_int_enable78;
+ i2c->hlc_int_dis = octeon_i2c_hlc_int_disable78;
+
+ irq_set_status_flags(i2c->irq, IRQ_NOAUTOEN);
+ irq_set_status_flags(i2c->hlc_irq, IRQ_NOAUTOEN);
+
+ result = devm_request_irq(&pdev->dev, i2c->hlc_irq,
+ octeon_i2c_hlc_isr78, 0,
+ DRV_NAME, i2c);
+ if (result < 0) {
+ dev_err(i2c->dev, "failed to attach interrupt\n");
+ goto out;
+ }
+ } else {
+ i2c->int_en = octeon_i2c_int_enable;
+ i2c->int_dis = octeon_i2c_int_disable;
+ i2c->hlc_int_en = octeon_i2c_hlc_int_enable;
+ i2c->hlc_int_dis = octeon_i2c_int_disable;
+ }
+
+ result = devm_request_irq(&pdev->dev, i2c->irq,
+ octeon_i2c_isr, 0, DRV_NAME, i2c);
+ if (result < 0) {
+ dev_err(i2c->dev, "failed to attach interrupt\n");
+ goto out;
+ }
+
+ if (OCTEON_IS_MODEL(OCTEON_CN38XX))
+ i2c->broken_irq_check = true;
+
+ result = octeon_i2c_init_lowlevel(i2c);
+ if (result) {
+ dev_err(i2c->dev, "init low level failed\n");
+ goto out;
+ }
+
+ octeon_i2c_set_clock(i2c);
+
+ i2c->adap = octeon_i2c_ops;
+ i2c->adap.timeout = msecs_to_jiffies(2);
+ i2c->adap.retries = 10;
+ i2c->adap.dev.parent = &pdev->dev;
+ i2c->adap.dev.of_node = node;
+ i2c_set_adapdata(&i2c->adap, i2c);
+ platform_set_drvdata(pdev, i2c);
+
+ result = i2c_add_adapter(&i2c->adap);
+ if (result < 0) {
+ dev_err(i2c->dev, "failed to add adapter\n");
+ goto out;
+ }
+ dev_info(i2c->dev, "probed\n");
+ return 0;
+
+out:
+ return result;
+};
+
+static int octeon_i2c_remove(struct platform_device *pdev)
+{
+ struct octeon_i2c *i2c = platform_get_drvdata(pdev);
+
+ i2c_del_adapter(&i2c->adap);
+ return 0;
+};
+
+static const struct of_device_id octeon_i2c_match[] = {
+ { .compatible = "cavium,octeon-3860-twsi", },
+ { .compatible = "cavium,octeon-7890-twsi", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, octeon_i2c_match);
+
+static struct platform_driver octeon_i2c_driver = {
+ .probe = octeon_i2c_probe,
+ .remove = octeon_i2c_remove,
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = octeon_i2c_match,
+ },
+};
+
+module_platform_driver(octeon_i2c_driver);
+
+MODULE_AUTHOR("Michael Lawnick <michael.lawnick.ext@xxxxxxx>");
+MODULE_DESCRIPTION("I2C-Bus adapter for Cavium OCTEON processors");
+MODULE_LICENSE("GPL");
diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c
deleted file mode 100644
index 444e8ed..0000000
--- a/drivers/i2c/busses/i2c-octeon.c
+++ /dev/null
@@ -1,1264 +0,0 @@
-/*
- * (C) Copyright 2009-2010
- * Nokia Siemens Networks, michael.lawnick.ext@xxxxxxx
- *
- * Portions Copyright (C) 2010 - 2016 Cavium, Inc.
- *
- * This is a driver for the i2c adapter in Cavium Networks' OCTEON processors.
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2. This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
- */
-
-#include <linux/atomic.h>
-#include <linux/platform_device.h>
-#include <linux/interrupt.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/delay.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/i2c.h>
-#include <linux/io.h>
-#include <linux/of.h>
-
-#include <asm/octeon/octeon.h>
-
-#define DRV_NAME "i2c-octeon"
-
-/* Register offsets */
-#define SW_TWSI 0x00
-#define TWSI_INT 0x10
-#define SW_TWSI_EXT 0x18
-
-/* Controller command patterns */
-#define SW_TWSI_V BIT_ULL(63) /* Valid bit */
-#define SW_TWSI_EIA BIT_ULL(61) /* Extended internal address */
-#define SW_TWSI_R BIT_ULL(56) /* Result or read bit */
-#define SW_TWSI_SOVR BIT_ULL(55) /* Size override */
-#define SW_TWSI_SIZE_SHIFT 52
-#define SW_TWSI_ADDR_SHIFT 40
-#define SW_TWSI_IA_SHIFT 32 /* Internal address */
-
-/* Controller opcode word (bits 60:57) */
-#define SW_TWSI_OP_SHIFT 57
-#define SW_TWSI_OP_7 (0ULL << SW_TWSI_OP_SHIFT)
-#define SW_TWSI_OP_7_IA (1ULL << SW_TWSI_OP_SHIFT)
-#define SW_TWSI_OP_10 (2ULL << SW_TWSI_OP_SHIFT)
-#define SW_TWSI_OP_10_IA (3ULL << SW_TWSI_OP_SHIFT)
-#define SW_TWSI_OP_TWSI_CLK (4ULL << SW_TWSI_OP_SHIFT)
-#define SW_TWSI_OP_EOP (6ULL << SW_TWSI_OP_SHIFT) /* Extended opcode */
-
-/* Controller extended opcode word (bits 34:32) */
-#define SW_TWSI_EOP_SHIFT 32
-#define SW_TWSI_EOP_TWSI_DATA (SW_TWSI_OP_EOP | 1ULL << SW_TWSI_EOP_SHIFT)
-#define SW_TWSI_EOP_TWSI_CTL (SW_TWSI_OP_EOP | 2ULL << SW_TWSI_EOP_SHIFT)
-#define SW_TWSI_EOP_TWSI_CLKCTL (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
-#define SW_TWSI_EOP_TWSI_STAT (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
-#define SW_TWSI_EOP_TWSI_RST (SW_TWSI_OP_EOP | 7ULL << SW_TWSI_EOP_SHIFT)
-
-/* Controller command and status bits */
-#define TWSI_CTL_CE 0x80 /* High level controller enable */
-#define TWSI_CTL_ENAB 0x40 /* Bus enable */
-#define TWSI_CTL_STA 0x20 /* Master-mode start, HW clears when done */
-#define TWSI_CTL_STP 0x10 /* Master-mode stop, HW clears when done */
-#define TWSI_CTL_IFLG 0x08 /* HW event, SW writes 0 to ACK */
-#define TWSI_CTL_AAK 0x04 /* Assert ACK */
-
-/* Some status values */
-#define STAT_ERROR 0x00
-#define STAT_START 0x08
-#define STAT_RSTART 0x10
-#define STAT_TXADDR_ACK 0x18
-#define STAT_TXADDR_NAK 0x20
-#define STAT_TXDATA_ACK 0x28
-#define STAT_TXDATA_NAK 0x30
-#define STAT_LOST_ARB_38 0x38
-#define STAT_RXADDR_ACK 0x40
-#define STAT_RXADDR_NAK 0x48
-#define STAT_RXDATA_ACK 0x50
-#define STAT_RXDATA_NAK 0x58
-#define STAT_SLAVE_60 0x60
-#define STAT_LOST_ARB_68 0x68
-#define STAT_SLAVE_70 0x70
-#define STAT_LOST_ARB_78 0x78
-#define STAT_SLAVE_80 0x80
-#define STAT_SLAVE_88 0x88
-#define STAT_GENDATA_ACK 0x90
-#define STAT_GENDATA_NAK 0x98
-#define STAT_SLAVE_A0 0xA0
-#define STAT_SLAVE_A8 0xA8
-#define STAT_LOST_ARB_B0 0xB0
-#define STAT_SLAVE_LOST 0xB8
-#define STAT_SLAVE_NAK 0xC0
-#define STAT_SLAVE_ACK 0xC8
-#define STAT_AD2W_ACK 0xD0
-#define STAT_AD2W_NAK 0xD8
-#define STAT_IDLE 0xF8
-
-/* TWSI_INT values */
-#define TWSI_INT_ST_INT BIT_ULL(0)
-#define TWSI_INT_TS_INT BIT_ULL(1)
-#define TWSI_INT_CORE_INT BIT_ULL(2)
-#define TWSI_INT_ST_EN BIT_ULL(4)
-#define TWSI_INT_TS_EN BIT_ULL(5)
-#define TWSI_INT_CORE_EN BIT_ULL(6)
-#define TWSI_INT_SDA_OVR BIT_ULL(8)
-#define TWSI_INT_SCL_OVR BIT_ULL(9)
-#define TWSI_INT_SDA BIT_ULL(10)
-#define TWSI_INT_SCL BIT_ULL(11)
-
-struct octeon_i2c {
- wait_queue_head_t queue;
- struct i2c_adapter adap;
- int irq;
- int hlc_irq; /* For cn7890 only */
- u32 twsi_freq;
- int sys_freq;
- void __iomem *twsi_base;
- struct device *dev;
- bool hlc_enabled;
- bool broken_irq_mode;
- bool broken_irq_check;
- void (*int_en)(struct octeon_i2c *);
- void (*int_dis)(struct octeon_i2c *);
- void (*hlc_int_en)(struct octeon_i2c *);
- void (*hlc_int_dis)(struct octeon_i2c *);
- atomic_t int_en_cnt;
- atomic_t hlc_int_en_cnt;
-};
-
-static int reset_how;
-
-static void writeqflush(u64 val, void __iomem *addr)
-{
- __raw_writeq(val, addr);
- __raw_readq(addr); /* wait for write to land */
-}
-
-/**
- * octeon_i2c_write_sw - write an I2C core register
- * @i2c: The struct octeon_i2c
- * @eop_reg: Register selector
- * @data: Value to be written
- *
- * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
- */
-static void octeon_i2c_write_sw(struct octeon_i2c *i2c, u64 eop_reg, u32 data)
-{
- u64 tmp;
-
- __raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + SW_TWSI);
- do {
- tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
- } while ((tmp & SW_TWSI_V) != 0);
-}
-
-/**
- * octeon_i2c_read_sw64 - read an I2C core register
- * @i2c: The struct octeon_i2c
- * @eop_reg: Register selector
- *
- * Returns the data.
- *
- * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
- */
-static u64 octeon_i2c_read_sw64(struct octeon_i2c *i2c, u64 eop_reg)
-{
- u64 tmp;
-
- __raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base + SW_TWSI);
- do {
- tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
- } while ((tmp & SW_TWSI_V) != 0);
-
- return tmp;
-}
-
-/**
- * octeon_i2c_read_sw - read lower bits of an I2C core register
- * @i2c: The struct octeon_i2c
- * @eop_reg: Register selector
- *
- * Returns the data.
- *
- * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
- */
-static u8 octeon_i2c_read_sw(struct octeon_i2c *i2c, u64 eop_reg)
-{
- return octeon_i2c_read_sw64(i2c, eop_reg) & 0xFF;
-}
-
-/**
- * octeon_i2c_write_int - write the TWSI_INT register
- * @i2c: The struct octeon_i2c
- * @data: Value to be written
- */
-static void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
-{
- writeqflush(data, i2c->twsi_base + TWSI_INT);
-}
-
-/**
- * octeon_i2c_int_enable - enable the CORE interrupt
- * @i2c: The struct octeon_i2c
- *
- * The interrupt will be asserted when there is non-STAT_IDLE state in
- * the SW_TWSI_EOP_TWSI_STAT register.
- */
-static void octeon_i2c_int_enable(struct octeon_i2c *i2c)
-{
- octeon_i2c_write_int(i2c, TWSI_INT_CORE_EN);
-}
-
-/* disable the CORE interrupt */
-static void octeon_i2c_int_disable(struct octeon_i2c *i2c)
-{
- /* clear TS/ST/IFLG events */
- octeon_i2c_write_int(i2c, 0);
-}
-
-static void octeon_i2c_disable_hlc(struct octeon_i2c *i2c)
-{
- if (!i2c->hlc_enabled)
- return;
-
- i2c->hlc_enabled = false;
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
-}
-
-/**
- * octeon_i2c_int_enable78 - enable the CORE interrupt
- * @i2c: The struct octeon_i2c
- *
- * The interrupt will be asserted when there is non-STAT_IDLE state in the
- * SW_TWSI_EOP_TWSI_STAT register.
- */
-static void octeon_i2c_int_enable78(struct octeon_i2c *i2c)
-{
- atomic_inc_return(&i2c->int_en_cnt);
- enable_irq(i2c->irq);
-}
-
-static void __octeon_i2c_irq_disable(atomic_t *cnt, int irq)
-{
- int count;
-
- /*
- * The interrupt can be disabled in two places, but we only
- * want to make the disable_irq_nosync() call once, so keep
- * track with the atomic variable.
- */
- count = atomic_dec_if_positive(cnt);
- if (count >= 0)
- disable_irq_nosync(irq);
-}
-
-/* disable the CORE interrupt */
-static void octeon_i2c_int_disable78(struct octeon_i2c *i2c)
-{
- __octeon_i2c_irq_disable(&i2c->int_en_cnt, i2c->irq);
-}
-
-/**
- * octeon_i2c_hlc_int_enable78 - enable the ST interrupt
- * @i2c: The struct octeon_i2c
- *
- * The interrupt will be asserted when there is non-STAT_IDLE state in
- * the SW_TWSI_EOP_TWSI_STAT register.
- */
-static void octeon_i2c_hlc_int_enable78(struct octeon_i2c *i2c)
-{
- atomic_inc_return(&i2c->hlc_int_en_cnt);
- enable_irq(i2c->hlc_irq);
-}
-
-/* disable the ST interrupt */
-static void octeon_i2c_hlc_int_disable78(struct octeon_i2c *i2c)
-{
- __octeon_i2c_irq_disable(&i2c->hlc_int_en_cnt, i2c->hlc_irq);
-}
-
-/**
- * octeon_i2c_unblock - unblock the bus
- * @i2c: The struct octeon_i2c
- *
- * If there was a reset while a device was driving 0 to bus, bus is blocked.
- * We toggle it free manually by some clock cycles and send a stop.
- */
-static void octeon_i2c_unblock(struct octeon_i2c *i2c)
-{
- int state, i;
-
- octeon_i2c_disable_hlc(i2c);
- dev_dbg(i2c->dev, "%s\n", __func__);
-
- /* cycle 8+1 clocks with SDA high */
- for (i = 0; i < 9; i++) {
- octeon_i2c_write_int(i2c, 0);
- udelay(5);
- state = __raw_readq(i2c->twsi_base + TWSI_INT);
- if (state & (TWSI_INT_SDA | TWSI_INT_SCL))
- break;
- octeon_i2c_write_int(i2c, TWSI_INT_SCL_OVR);
- udelay(5);
- }
- /* hand-crank a STOP */
- octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR | TWSI_INT_SCL_OVR);
- udelay(5);
- octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR);
- udelay(5);
- octeon_i2c_write_int(i2c, 0);
-}
-
-/* interrupt service routine */
-static irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
-{
- struct octeon_i2c *i2c = dev_id;
-
- i2c->int_dis(i2c);
- wake_up(&i2c->queue);
-
- return IRQ_HANDLED;
-}
-
-/* HLC interrupt service routine */
-static irqreturn_t octeon_i2c_hlc_isr78(int irq, void *dev_id)
-{
- struct octeon_i2c *i2c = dev_id;
-
- i2c->hlc_int_dis(i2c);
- wake_up(&i2c->queue);
-
- return IRQ_HANDLED;
-}
-
-static u64 octeon_i2c_read_ctl(struct octeon_i2c *i2c)
-{
- return octeon_i2c_read_sw64(i2c, SW_TWSI_EOP_TWSI_CTL);
-}
-
-static int octeon_i2c_test_iflg(struct octeon_i2c *i2c)
-{
- return (octeon_i2c_read_ctl(i2c) & TWSI_CTL_IFLG) != 0;
-}
-
-#define I2C_OCTEON_IFLG_WAIT 80 /* microseconds */
-
-/*
- * Wait-helper which addresses the delayed-IFLAG problem by re-polling for
- * missing TWSI_CTL[IFLG] a few us later, when irq has signalled an event,
- * but none found. Skip this re-poll on the first (non-wakeup) call.
- */
-static int poll_iflg(struct octeon_i2c *i2c, int *first_p)
-{
- int iflg = octeon_i2c_test_iflg(i2c);
-
- if (iflg)
- return 1;
- if (*first_p)
- *first_p = 0;
- else {
- usleep_range(I2C_OCTEON_IFLG_WAIT, 2 * I2C_OCTEON_IFLG_WAIT);
- iflg = octeon_i2c_test_iflg(i2c);
- }
- return iflg;
-}
-
-/**
- * octeon_i2c_wait - wait for the IFLG to be set
- * @i2c: The struct octeon_i2c
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_wait(struct octeon_i2c *i2c)
-{
- long time_left;
- int first = 1;
-
- if (i2c->broken_irq_mode) {
- /*
- * Some chip revisions seem to not assert the irq in
- * the interrupt controller. So we must poll for the
- * IFLG change.
- */
- u64 end = get_jiffies_64() + i2c->adap.timeout;
-
- while (!octeon_i2c_test_iflg(i2c) &&
- time_before64(get_jiffies_64(), end))
- udelay(50);
-
- return octeon_i2c_test_iflg(i2c) ? 0 : -ETIMEDOUT;
- }
-
- i2c->int_en(i2c);
- time_left = wait_event_timeout(i2c->queue, poll_iflg(i2c, &first),
- i2c->adap.timeout);
- i2c->int_dis(i2c);
-
- if (time_left <= 0 && i2c->broken_irq_check &&
- octeon_i2c_test_iflg(i2c)) {
- dev_err(i2c->dev,
- "broken irq connection detected, switching to polling mode.\n");
- i2c->broken_irq_mode = true;
- return 0;
- }
- if (!time_left) {
- dev_dbg(i2c->dev, "%s: timeout\n", __func__);
- return -ETIMEDOUT;
- }
-
- return 0;
-}
-
-/*
- * Cleanup low-level state & enable high-level.
- * Returns -EAGAIN if low-level state could not be cleaned.
- */
-static int octeon_i2c_enable_hlc(struct octeon_i2c *i2c)
-{
- int try = 0, ret = 0;
- u64 val;
-
- if (i2c->hlc_enabled)
- return 0;
- i2c->hlc_enabled = true;
-
- while (1) {
- val = octeon_i2c_read_ctl(i2c) & (TWSI_CTL_STA | TWSI_CTL_STP);
- if (!val)
- break;
-
- /* clear IFLG event */
- if (val & TWSI_CTL_IFLG)
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
-
- if (try++ > 100) {
- pr_err("%s: giving up\n", __func__);
- ret = -EAGAIN;
- break;
- }
-
- /* spin until any start/stop has finished */
- udelay(10);
- }
-
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
- TWSI_CTL_CE | TWSI_CTL_AAK | TWSI_CTL_ENAB);
- return ret;
-}
-
-static int octeon_i2c_lost_arb(u8 code, int final_read)
-{
- switch (code) {
- /* Arbitration lost */
- case STAT_LOST_ARB_38:
- case STAT_LOST_ARB_68:
- case STAT_LOST_ARB_78:
- case STAT_LOST_ARB_B0:
- return -EAGAIN;
-
- /* Being addressed as slave, should back off & listen */
- case STAT_SLAVE_60:
- case STAT_SLAVE_70:
- case STAT_GENDATA_ACK:
- case STAT_GENDATA_NAK:
- return -EIO;
-
- /* Core busy as slave */
- case STAT_SLAVE_80:
- case STAT_SLAVE_88:
- case STAT_SLAVE_A0:
- case STAT_SLAVE_A8:
- case STAT_SLAVE_LOST:
- case STAT_SLAVE_NAK:
- case STAT_SLAVE_ACK:
- return -EIO;
-
- /* ACK allowed on pre-terminal bytes only */
- case STAT_RXDATA_ACK:
- if (!final_read)
- return 0;
- return -EAGAIN;
-
- /* NAK allowed on terminal byte only */
- case STAT_RXDATA_NAK:
- if (final_read)
- return 0;
- return -EAGAIN;
- case STAT_TXDATA_NAK:
- case STAT_TXADDR_NAK:
- case STAT_RXADDR_NAK:
- case STAT_AD2W_NAK:
- return -EAGAIN;
- }
- return 0;
-}
-
-static int check_arb(struct octeon_i2c *i2c, int final_read)
-{
- return octeon_i2c_lost_arb(octeon_i2c_read_sw(i2c,
- SW_TWSI_EOP_TWSI_STAT), final_read);
-}
-
-/* send STOP to the bus */
-static void octeon_i2c_stop(struct octeon_i2c *i2c)
-{
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
- TWSI_CTL_ENAB | TWSI_CTL_STP);
-}
-
-static bool octeon_i2c_hlc_test_ready(struct octeon_i2c *i2c)
-{
- u64 val = __raw_readq(i2c->twsi_base + SW_TWSI);
-
- return (val & SW_TWSI_V) == 0;
-}
-
-static void octeon_i2c_hlc_int_enable(struct octeon_i2c *i2c)
-{
- octeon_i2c_write_int(i2c, TWSI_INT_ST_EN);
-}
-
-static void octeon_i2c_hlc_int_clear(struct octeon_i2c *i2c)
-{
- /* clear ST/TS events, listen for neither */
- octeon_i2c_write_int(i2c, TWSI_INT_ST_INT | TWSI_INT_TS_INT);
-}
-
-/**
- * octeon_i2c_hlc_wait - wait for an HLC operation to complete
- * @i2c: The struct octeon_i2c
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
-{
- int time_left;
-
- if (i2c->broken_irq_mode) {
- /*
- * Some cn38xx boards did not assert the irq in
- * the interrupt controller. So we must poll for the
- * IFLG change.
- */
- u64 end = get_jiffies_64() + i2c->adap.timeout;
-
- while (!octeon_i2c_hlc_test_ready(i2c) &&
- time_before64(get_jiffies_64(), end))
- udelay(50);
-
- return octeon_i2c_hlc_test_ready(i2c) ? 0 : -ETIMEDOUT;
- }
-
- i2c->hlc_int_en(i2c);
- time_left = wait_event_interruptible_timeout(i2c->queue,
- octeon_i2c_hlc_test_ready(i2c),
- i2c->adap.timeout);
- i2c->hlc_int_dis(i2c);
- if (!time_left)
- octeon_i2c_hlc_int_clear(i2c);
-
- if (time_left <= 0 && i2c->broken_irq_check &&
- octeon_i2c_hlc_test_ready(i2c)) {
- dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n");
- i2c->broken_irq_mode = true;
- return 0;
- }
-
- if (!time_left) {
- dev_dbg(i2c->dev, "%s: timeout\n", __func__);
- return -ETIMEDOUT;
- }
- if (time_left < 0) {
- dev_dbg(i2c->dev, "%s: wait interrupted\n", __func__);
- return time_left;
- }
- return 0;
-}
-
-/* high-level-controller pure read of up to 8 bytes */
-static int octeon_i2c_simple_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
-{
- int i, j, ret = 0;
- u64 cmd;
-
- octeon_i2c_enable_hlc(i2c);
- cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
- /* SIZE */
- cmd |= (u64) (msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
- /* A */
- cmd |= (u64) (msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
-
- if (msgs[0].flags & I2C_M_TEN)
- cmd |= SW_TWSI_OP_10;
- else
- cmd |= SW_TWSI_OP_7;
-
- octeon_i2c_hlc_int_clear(i2c);
- __raw_writeq(cmd, i2c->twsi_base + SW_TWSI);
-
- ret = octeon_i2c_hlc_wait(i2c);
- if (ret)
- goto err;
-
- cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
- if ((cmd & SW_TWSI_R) == 0)
- return -EAGAIN;
-
- for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
- msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
-
- if (msgs[0].len > 4) {
- cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
- for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
- msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
- }
-
-err:
- return ret;
-}
-
-/* high-level-controller pure write of up to 8 bytes */
-static int octeon_i2c_simple_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
-{
- int i, j, ret = 0;
- u64 cmd;
-
- octeon_i2c_enable_hlc(i2c);
- octeon_i2c_hlc_int_clear(i2c);
-
- ret = check_arb(i2c, false);
- if (ret)
- goto err;
-
- cmd = SW_TWSI_V | SW_TWSI_SOVR;
- /* SIZE */
- cmd |= (u64) (msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
- /* A */
- cmd |= (u64) (msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
-
- if (msgs[0].flags & I2C_M_TEN)
- cmd |= SW_TWSI_OP_10;
- else
- cmd |= SW_TWSI_OP_7;
-
- for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--)
- cmd |= (u64)msgs[0].buf[j] << (8 * i);
-
- if (msgs[0].len > 4) {
- u64 ext = 0;
-
- for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
- ext |= (u64) msgs[0].buf[j] << (8 * i);
- writeqflush(ext, i2c->twsi_base + SW_TWSI_EXT);
- }
-
- writeqflush(cmd, i2c->twsi_base + SW_TWSI);
-
- ret = octeon_i2c_hlc_wait(i2c);
- if (ret)
- goto err;
-
- cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
- if ((cmd & SW_TWSI_R) == 0)
- return -EAGAIN;
-
- ret = check_arb(i2c, false);
-
-err:
- return ret;
-}
-
-/* high-level-controller composite write+read, msg0=addr, msg1=data */
-static int octeon_i2c_ia_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
-{
- int i, j, ret = 0;
- u64 cmd;
-
- octeon_i2c_enable_hlc(i2c);
-
- cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
- /* SIZE */
- cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
- /* A */
- cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
-
- if (msgs[0].flags & I2C_M_TEN)
- cmd |= SW_TWSI_OP_10_IA;
- else
- cmd |= SW_TWSI_OP_7_IA;
-
- if (msgs[0].len == 2) {
- u64 ext = 0;
-
- cmd |= SW_TWSI_EIA;
- ext = (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
- cmd |= (u64) msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
- __raw_writeq(ext, i2c->twsi_base + SW_TWSI_EXT);
- } else
- cmd |= (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
-
- octeon_i2c_hlc_int_clear(i2c);
- writeqflush(cmd, i2c->twsi_base + SW_TWSI);
-
- ret = octeon_i2c_hlc_wait(i2c);
- if (ret)
- goto err;
-
- cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
- if ((cmd & SW_TWSI_R) == 0)
- return -EAGAIN;
-
- for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
- msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
-
- if (msgs[1].len > 4) {
- cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
- for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
- msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
- }
-
-err:
- return ret;
-}
-
-/* high-level-controller composite write+write, m[0]len<=2, m[1]len<=8 */
-static int octeon_i2c_ia_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
-{
- bool set_ext = false;
- int i, j, ret = 0;
- u64 cmd, ext = 0;
-
- octeon_i2c_enable_hlc(i2c);
-
- cmd = SW_TWSI_V | SW_TWSI_SOVR;
- /* SIZE */
- cmd |= (u64) (msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
- /* A */
- cmd |= (u64) (msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
-
- if (msgs[0].flags & I2C_M_TEN)
- cmd |= SW_TWSI_OP_10_IA;
- else
- cmd |= SW_TWSI_OP_7_IA;
-
- if (msgs[0].len == 2) {
- cmd |= SW_TWSI_EIA;
- ext |= (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
- set_ext = true;
- cmd |= (u64) msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
- } else
- cmd |= (u64) msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
-
- for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--)
- cmd |= (u64) msgs[1].buf[j] << (8 * i);
-
- if (msgs[1].len > 4) {
- for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
- ext |= (u64)msgs[1].buf[j] << (8 * i);
- set_ext = true;
- }
- if (set_ext)
- writeqflush(ext, i2c->twsi_base + SW_TWSI_EXT);
-
- octeon_i2c_hlc_int_clear(i2c);
- writeqflush(cmd, i2c->twsi_base + SW_TWSI);
-
- ret = octeon_i2c_hlc_wait(i2c);
- if (ret)
- goto err;
-
- cmd = octeon_i2c_read_sw64(i2c, SW_TWSI_EOP_TWSI_STAT);
- if ((cmd & SW_TWSI_R) == 0)
- return -EAGAIN;
- ret = octeon_i2c_lost_arb(cmd, false);
-
-err:
- return ret;
-}
-
-/* calculate and set clock divisors */
-static void octeon_i2c_set_clock(struct octeon_i2c *i2c)
-{
- int tclk, thp_base, inc, thp_idx, mdiv_idx, ndiv_idx, foscl, diff;
- int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = 1000000;
-
- for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
- /*
- * An mdiv value of less than 2 seems to not work well
- * with ds1337 RTCs, so we constrain it to larger values.
- */
- for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
- /*
- * For given ndiv and mdiv values check the
- * two closest thp values.
- */
- tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
- tclk *= (1 << ndiv_idx);
- thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
-
- for (inc = 0; inc <= 1; inc++) {
- thp_idx = thp_base + inc;
- if (thp_idx < 5 || thp_idx > 0xff)
- continue;
-
- foscl = i2c->sys_freq / (2 * (thp_idx + 1));
- foscl = foscl / (1 << ndiv_idx);
- foscl = foscl / (mdiv_idx + 1) / 10;
- diff = abs(foscl - i2c->twsi_freq);
- if (diff < delta_hz) {
- delta_hz = diff;
- thp = thp_idx;
- mdiv = mdiv_idx;
- ndiv = ndiv_idx;
- }
- }
- }
- }
- octeon_i2c_write_sw(i2c, SW_TWSI_OP_TWSI_CLK, thp);
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
-}
-
-static int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c)
-{
- u8 status = 0;
- int tries;
-
- /* reset controller */
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_RST, 0);
-
- for (tries = 10; tries && status != STAT_IDLE; tries--) {
- udelay(1);
- status = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
- }
-
- if (status != STAT_IDLE) {
- dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n",
- __func__, status);
- return -EIO;
- }
-
- /* toggle twice to force both teardowns */
- octeon_i2c_enable_hlc(i2c);
- octeon_i2c_disable_hlc(i2c);
- return 0;
-}
-
-/*
- * TWSI state seems stuck. Not sure if it's TWSI-engine state or something
- * else on bus. The initial _stop() is always harmless, it just resets state
- * machine, does not _transmit_ STOP unless engine was active.
- */
-static int start_unstick(struct octeon_i2c *i2c)
-{
- octeon_i2c_stop(i2c);
-
- /*
- * Response is escalated over successive calls,
- * as EAGAIN provokes retries from i2c/core.
- */
- switch (reset_how++ % 4) {
- case 0:
- /* just the stop above */
- break;
- case 1:
- /*
- * Controller refused to send start flag. May be a
- * client is holding SDA low? Let's try to free it.
- */
- octeon_i2c_unblock(i2c);
- break;
- case 2:
- /* re-init our TWSI hardware */
- octeon_i2c_init_lowlevel(i2c);
- break;
- default:
- /* retry in caller */
- reset_how = 0;
- return -EAGAIN;
- }
- return 0;
-}
-
-/**
- * octeon_i2c_start - send START to the bus
- * @i2c: The struct octeon_i2c
- * @first: first msg in combined operation?
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_start(struct octeon_i2c *i2c, int first)
-{
- int result;
- u8 data;
-
- octeon_i2c_disable_hlc(i2c);
-
- while (1) {
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
- TWSI_CTL_ENAB | TWSI_CTL_STA);
-
- result = octeon_i2c_wait(i2c);
- data = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
-
- switch (data) {
- case STAT_START:
- case STAT_RSTART:
- if (!first)
- return -EAGAIN;
- reset_how = 0;
- return 0;
- case STAT_RXADDR_ACK:
- if (first)
- return -EAGAIN;
- return start_unstick(i2c);
- /*
- * case STAT_IDLE:
- * case STAT_ERROR:
- */
- default:
- if (!first)
- return -EAGAIN;
- start_unstick(i2c);
- }
- }
- return 0;
-}
-
-/**
- * octeon_i2c_read - receive data from the bus via low-level controller
- * @i2c: The struct octeon_i2c
- * @target: Target address
- * @data: Pointer to the location to store the data
- * @rlength: Length of the data
- * @phase: which phase of a combined operation.
- * @recv_len: flag for length byte
- *
- * The address is sent over the bus, then the data is read.
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_read(struct octeon_i2c *i2c, int target, u8 *data,
- u16 *rlength, bool first, bool last, bool recv_len)
-{
- u8 ctl = TWSI_CTL_ENAB | TWSI_CTL_AAK;
- int i, result, length = *rlength;
- u8 tmp;
-
- if (length < 1)
- return -EINVAL;
-
- result = octeon_i2c_start(i2c, first);
- if (result)
- return result;
-
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, (target << 1) | 1);
-
- for (i = 0; i < length; ) {
- tmp = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
- result = octeon_i2c_lost_arb(tmp, !(ctl & TWSI_CTL_AAK));
- if (result)
- return result;
-
- switch (tmp) {
- case STAT_RXDATA_ACK:
- case STAT_RXDATA_NAK:
- data[i++] = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_DATA);
- }
-
-
- /* NAK last recv'd byte, as a no-more-please */
- if (last && i == length - 1)
- ctl &= ~TWSI_CTL_AAK;
-
- /* clr iflg to allow next event */
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, ctl);
- result = octeon_i2c_wait(i2c);
- if (result)
- return result;
- if (recv_len && i == 0) {
- if (data[i] > I2C_SMBUS_BLOCK_MAX + 1) {
- dev_err(i2c->dev,
- "%s: read len > I2C_SMBUS_BLOCK_MAX %d\n",
- __func__, data[i]);
- return -EPROTO;
- }
- length += data[i];
- }
- }
- *rlength = length;
- return 0;
-}
-
-/**
- * octeon_i2c_write - send data to the bus via low-level controller
- * @i2c: The struct octeon_i2c
- * @target: Target address
- * @data: Pointer to the data to be sent
- * @length: Length of the data
- * @last: is last msg in combined operation?
- *
- * The address is sent over the bus, then the data.
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_write(struct octeon_i2c *i2c, int target,
- const u8 *data, int length, int first, int last)
-{
- int i, result;
-
- result = octeon_i2c_start(i2c, first);
- if (result)
- return result;
-
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, target << 1);
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
-
- result = octeon_i2c_wait(i2c);
- if (result)
- return result;
-
- for (i = 0; i < length; i++) {
- result = check_arb(i2c, false);
- if (result)
- return result;
-
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, data[i]);
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
-
- result = octeon_i2c_wait(i2c);
- if (result)
- return result;
- result = check_arb(i2c, false);
- if (result)
- return result;
- }
-
- return 0;
-}
-
-/**
- * octeon_i2c_xfer - The driver's master_xfer function
- * @adap: Pointer to the i2c_adapter structure
- * @msgs: Pointer to the messages to be processed
- * @num: Length of the MSGS array
- *
- * Returns the number of messages processed, or a negative errno on failure.
- */
-static int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
- int num)
-{
- struct octeon_i2c *i2c = i2c_get_adapdata(adap);
- int i, ret = 0;
-
- if (num == 1) {
- if (msgs[0].len > 0 && msgs[0].len <= 8) {
- if (msgs[0].flags & I2C_M_RD)
- ret = octeon_i2c_simple_read(i2c, msgs);
- else
- ret = octeon_i2c_simple_write(i2c, msgs);
- goto out;
- }
- } else if (num == 2) {
- if ((msgs[0].flags & I2C_M_RD) == 0 &&
- (msgs[1].flags & I2C_M_RECV_LEN) == 0 &&
- msgs[0].len > 0 && msgs[0].len <= 2 &&
- msgs[1].len > 0 && msgs[1].len <= 8 &&
- msgs[0].addr == msgs[1].addr) {
- if (msgs[1].flags & I2C_M_RD)
- ret = octeon_i2c_ia_read(i2c, msgs);
- else
- ret = octeon_i2c_ia_write(i2c, msgs);
- goto out;
- }
- }
-
- for (i = 0; ret == 0 && i < num; i++) {
- struct i2c_msg *pmsg = &msgs[i];
- bool last = (i == (num - 1));
-
- dev_dbg(i2c->dev,
- "Doing %s %d byte(s) to/from 0x%02x - %d of %d messages\n",
- pmsg->flags & I2C_M_RD ? "read" : "write",
- pmsg->len, pmsg->addr, i + 1, num);
- if (pmsg->flags & I2C_M_RD)
- ret = octeon_i2c_read(i2c, pmsg->addr, pmsg->buf,
- &pmsg->len, !i, last,
- pmsg->flags & I2C_M_RECV_LEN);
- else
- ret = octeon_i2c_write(i2c, pmsg->addr, pmsg->buf,
- pmsg->len, !i, last);
- }
- octeon_i2c_stop(i2c);
-out:
- return (ret != 0) ? ret : num;
-}
-
-static u32 octeon_i2c_functionality(struct i2c_adapter *adap)
-{
- return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
- I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_SMBUS_BLOCK_PROC_CALL;
-}
-
-static const struct i2c_algorithm octeon_i2c_algo = {
- .master_xfer = octeon_i2c_xfer,
- .functionality = octeon_i2c_functionality,
-};
-
-static struct i2c_adapter octeon_i2c_ops = {
- .owner = THIS_MODULE,
- .name = "OCTEON adapter",
- .algo = &octeon_i2c_algo,
-};
-
-static int octeon_i2c_probe(struct platform_device *pdev)
-{
- struct device_node *node = pdev->dev.of_node;
- int irq, result = 0, hlc_irq = 0;
- struct resource *res_mem;
- struct octeon_i2c *i2c;
- bool cn78xx_style;
-
- cn78xx_style = of_device_is_compatible(node, "cavium,octeon-7890-twsi");
- if (cn78xx_style) {
- hlc_irq = platform_get_irq(pdev, 0);
- if (hlc_irq < 0)
- return hlc_irq;
-
- irq = platform_get_irq(pdev, 2);
- if (irq < 0)
- return irq;
- } else {
- /* All adaptors have an irq. */
- irq = platform_get_irq(pdev, 0);
- if (irq < 0)
- return irq;
- }
-
- i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
- if (!i2c) {
- result = -ENOMEM;
- goto out;
- }
- i2c->dev = &pdev->dev;
-
- res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- i2c->twsi_base = devm_ioremap_resource(&pdev->dev, res_mem);
- if (IS_ERR(i2c->twsi_base)) {
- result = PTR_ERR(i2c->twsi_base);
- goto out;
- }
-
- /*
- * "clock-rate" is a legacy binding, the official binding is
- * "clock-frequency". Try the official one first and then
- * fall back if it doesn't exist.
- */
- if (of_property_read_u32(node, "clock-frequency", &i2c->twsi_freq) &&
- of_property_read_u32(node, "clock-rate", &i2c->twsi_freq)) {
- dev_err(i2c->dev,
- "no I2C 'clock-rate' or 'clock-frequency' property\n");
- result = -ENXIO;
- goto out;
- }
-
- i2c->sys_freq = octeon_get_io_clock_rate();
-
- init_waitqueue_head(&i2c->queue);
-
- i2c->irq = irq;
-
- if (cn78xx_style) {
- i2c->hlc_irq = hlc_irq;
-
- i2c->int_en = octeon_i2c_int_enable78;
- i2c->int_dis = octeon_i2c_int_disable78;
- i2c->hlc_int_en = octeon_i2c_hlc_int_enable78;
- i2c->hlc_int_dis = octeon_i2c_hlc_int_disable78;
-
- irq_set_status_flags(i2c->irq, IRQ_NOAUTOEN);
- irq_set_status_flags(i2c->hlc_irq, IRQ_NOAUTOEN);
-
- result = devm_request_irq(&pdev->dev, i2c->hlc_irq,
- octeon_i2c_hlc_isr78, 0,
- DRV_NAME, i2c);
- if (result < 0) {
- dev_err(i2c->dev, "failed to attach interrupt\n");
- goto out;
- }
- } else {
- i2c->int_en = octeon_i2c_int_enable;
- i2c->int_dis = octeon_i2c_int_disable;
- i2c->hlc_int_en = octeon_i2c_hlc_int_enable;
- i2c->hlc_int_dis = octeon_i2c_int_disable;
- }
-
- result = devm_request_irq(&pdev->dev, i2c->irq,
- octeon_i2c_isr, 0, DRV_NAME, i2c);
- if (result < 0) {
- dev_err(i2c->dev, "failed to attach interrupt\n");
- goto out;
- }
-
- if (OCTEON_IS_MODEL(OCTEON_CN38XX))
- i2c->broken_irq_check = true;
-
- result = octeon_i2c_init_lowlevel(i2c);
- if (result) {
- dev_err(i2c->dev, "init low level failed\n");
- goto out;
- }
-
- octeon_i2c_set_clock(i2c);
-
- i2c->adap = octeon_i2c_ops;
- i2c->adap.timeout = msecs_to_jiffies(2);
- i2c->adap.retries = 10;
- i2c->adap.dev.parent = &pdev->dev;
- i2c->adap.dev.of_node = node;
- i2c_set_adapdata(&i2c->adap, i2c);
- platform_set_drvdata(pdev, i2c);
-
- result = i2c_add_adapter(&i2c->adap);
- if (result < 0) {
- dev_err(i2c->dev, "failed to add adapter\n");
- goto out;
- }
- dev_info(i2c->dev, "probed\n");
- return 0;
-
-out:
- return result;
-};
-
-static int octeon_i2c_remove(struct platform_device *pdev)
-{
- struct octeon_i2c *i2c = platform_get_drvdata(pdev);
-
- i2c_del_adapter(&i2c->adap);
- return 0;
-};
-
-static const struct of_device_id octeon_i2c_match[] = {
- { .compatible = "cavium,octeon-3860-twsi", },
- { .compatible = "cavium,octeon-7890-twsi", },
- {},
-};
-MODULE_DEVICE_TABLE(of, octeon_i2c_match);
-
-static struct platform_driver octeon_i2c_driver = {
- .probe = octeon_i2c_probe,
- .remove = octeon_i2c_remove,
- .driver = {
- .name = DRV_NAME,
- .of_match_table = octeon_i2c_match,
- },
-};
-
-module_platform_driver(octeon_i2c_driver);
-
-MODULE_AUTHOR("Michael Lawnick <michael.lawnick.ext@xxxxxxx>");
-MODULE_DESCRIPTION("I2C-Bus adapter for Cavium OCTEON processors");
-MODULE_LICENSE("GPL");
--
1.9.1