[PATCH v8 1/2] i2c: i2c-qcom-geni: Add bus driver for the Qualcomm GENI I2C controller

From: Karthikeyan Ramasubramanian
Date: Mon Jul 30 2018 - 13:24:13 EST


This bus driver supports the GENI based i2c hardware controller in the
Qualcomm SOCs. The Qualcomm Generic Interface (GENI) is a programmable
module supporting a wide range of serial interfaces including I2C. The
driver supports FIFO mode and DMA mode of transfer and switches modes
dynamically depending on the size of the transfer.

Signed-off-by: Karthikeyan Ramasubramanian <kramasub@xxxxxxxxxxxxxx>
Signed-off-by: Sagar Dharia <sdharia@xxxxxxxxxxxxxx>
Signed-off-by: Girish Mahadevan <girishm@xxxxxxxxxxxxxx>
Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Reviewed-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
Tested-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
---
drivers/i2c/busses/Kconfig | 13 +
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-qcom-geni.c | 653 +++++++++++++++++++++++++++++++++++++
3 files changed, 667 insertions(+)
create mode 100644 drivers/i2c/busses/i2c-qcom-geni.c

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 4f8df2e..d219b5a 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -828,6 +828,19 @@ config I2C_PXA_SLAVE
is necessary for systems where the PXA may be a target on the
I2C bus.

+config I2C_QCOM_GENI
+ tristate "Qualcomm Technologies Inc.'s GENI based I2C controller"
+ depends on ARCH_QCOM || COMPILE_TEST
+ depends on QCOM_GENI_SE
+ help
+ This driver supports GENI serial engine based I2C controller in
+ master mode on the Qualcomm Technologies Inc.'s SoCs. If you say
+ yes to this option, support will be included for the built-in I2C
+ interface on the Qualcomm Technologies Inc.'s SoCs.
+
+ This driver can also be built as a module. If so, the module
+ will be called i2c-qcom-geni.
+
config I2C_QUP
tristate "Qualcomm QUP based I2C controller"
depends on ARCH_QCOM
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 5a86914..3e836cf 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -83,6 +83,7 @@ obj-$(CONFIG_I2C_PNX) += i2c-pnx.o
obj-$(CONFIG_I2C_PUV3) += i2c-puv3.o
obj-$(CONFIG_I2C_PXA) += i2c-pxa.o
obj-$(CONFIG_I2C_PXA_PCI) += i2c-pxa-pci.o
+obj-$(CONFIG_I2C_QCOM_GENI) += i2c-qcom-geni.o
obj-$(CONFIG_I2C_QUP) += i2c-qup.o
obj-$(CONFIG_I2C_RIIC) += i2c-riic.o
obj-$(CONFIG_I2C_RK3X) += i2c-rk3x.o
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
new file mode 100644
index 0000000..9a718b2
--- /dev/null
+++ b/drivers/i2c/busses/i2c-qcom-geni.c
@@ -0,0 +1,653 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
+
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/qcom-geni-se.h>
+#include <linux/spinlock.h>
+
+#define SE_I2C_TX_TRANS_LEN 0x26c
+#define SE_I2C_RX_TRANS_LEN 0x270
+#define SE_I2C_SCL_COUNTERS 0x278
+
+#define SE_I2C_ERR (M_CMD_OVERRUN_EN | M_ILLEGAL_CMD_EN | M_CMD_FAILURE_EN |\
+ M_GP_IRQ_1_EN | M_GP_IRQ_3_EN | M_GP_IRQ_4_EN)
+#define SE_I2C_ABORT BIT(1)
+
+/* M_CMD OP codes for I2C */
+#define I2C_WRITE 0x1
+#define I2C_READ 0x2
+#define I2C_WRITE_READ 0x3
+#define I2C_ADDR_ONLY 0x4
+#define I2C_BUS_CLEAR 0x6
+#define I2C_STOP_ON_BUS 0x7
+/* M_CMD params for I2C */
+#define PRE_CMD_DELAY BIT(0)
+#define TIMESTAMP_BEFORE BIT(1)
+#define STOP_STRETCH BIT(2)
+#define TIMESTAMP_AFTER BIT(3)
+#define POST_COMMAND_DELAY BIT(4)
+#define IGNORE_ADD_NACK BIT(6)
+#define READ_FINISHED_WITH_ACK BIT(7)
+#define BYPASS_ADDR_PHASE BIT(8)
+#define SLV_ADDR_MSK GENMASK(15, 9)
+#define SLV_ADDR_SHFT 9
+/* I2C SCL COUNTER fields */
+#define HIGH_COUNTER_MSK GENMASK(29, 20)
+#define HIGH_COUNTER_SHFT 20
+#define LOW_COUNTER_MSK GENMASK(19, 10)
+#define LOW_COUNTER_SHFT 10
+#define CYCLE_COUNTER_MSK GENMASK(9, 0)
+
+enum geni_i2c_err_code {
+ GP_IRQ0,
+ NACK,
+ GP_IRQ2,
+ BUS_PROTO,
+ ARB_LOST,
+ GP_IRQ5,
+ GENI_OVERRUN,
+ GENI_ILLEGAL_CMD,
+ GENI_ABORT_DONE,
+ GENI_TIMEOUT,
+};
+
+#define DM_I2C_CB_ERR ((BIT(NACK) | BIT(BUS_PROTO) | BIT(ARB_LOST)) \
+ << 5)
+
+#define I2C_AUTO_SUSPEND_DELAY 250
+#define KHZ(freq) (1000 * freq)
+#define PACKING_BYTES_PW 4
+
+#define ABORT_TIMEOUT HZ
+#define XFER_TIMEOUT HZ
+#define RST_TIMEOUT HZ
+
+struct geni_i2c_dev {
+ struct geni_se se;
+ u32 tx_wm;
+ int irq;
+ int err;
+ struct i2c_adapter adap;
+ struct completion done;
+ struct i2c_msg *cur;
+ int cur_wr;
+ int cur_rd;
+ spinlock_t lock;
+ u32 clk_freq_out;
+ const struct geni_i2c_clk_fld *clk_fld;
+};
+
+struct geni_i2c_err_log {
+ int err;
+ const char *msg;
+};
+
+static const struct geni_i2c_err_log gi2c_log[] = {
+ [GP_IRQ0] = {-EIO, "Unknown I2C err GP_IRQ0"},
+ [NACK] = {-ENXIO, "NACK: slv unresponsive, check its power/reset-ln"},
+ [GP_IRQ2] = {-EIO, "Unknown I2C err GP IRQ2"},
+ [BUS_PROTO] = {-EPROTO, "Bus proto err, noisy/unepxected start/stop"},
+ [ARB_LOST] = {-EAGAIN, "Bus arbitration lost, clock line undriveable"},
+ [GP_IRQ5] = {-EIO, "Unknown I2C err GP IRQ5"},
+ [GENI_OVERRUN] = {-EIO, "Cmd overrun, check GENI cmd-state machine"},
+ [GENI_ILLEGAL_CMD] = {-EIO, "Illegal cmd, check GENI cmd-state machine"},
+ [GENI_ABORT_DONE] = {-ETIMEDOUT, "Abort after timeout successful"},
+ [GENI_TIMEOUT] = {-ETIMEDOUT, "I2C TXN timed out"},
+};
+
+struct geni_i2c_clk_fld {
+ u32 clk_freq_out;
+ u8 clk_div;
+ u8 t_high_cnt;
+ u8 t_low_cnt;
+ u8 t_cycle_cnt;
+};
+
+/*
+ * Hardware uses the underlying formula to calculate time periods of
+ * SCL clock cycle. Firmware uses some additional cycles excluded from the
+ * below formula and it is confirmed that the time periods are within
+ * specification limits.
+ *
+ * time of high period of SCL: t_high = (t_high_cnt * clk_div) / source_clock
+ * time of low period of SCL: t_low = (t_low_cnt * clk_div) / source_clock
+ * time of full period of SCL: t_cycle = (t_cycle_cnt * clk_div) / source_clock
+ * clk_freq_out = t / t_cycle
+ * source_clock = 19.2 MHz
+ */
+static const struct geni_i2c_clk_fld geni_i2c_clk_map[] = {
+ {KHZ(100), 7, 10, 11, 26},
+ {KHZ(400), 2, 5, 12, 24},
+ {KHZ(1000), 1, 3, 9, 18},
+};
+
+static int geni_i2c_clk_map_idx(struct geni_i2c_dev *gi2c)
+{
+ int i;
+ const struct geni_i2c_clk_fld *itr = geni_i2c_clk_map;
+
+ for (i = 0; i < ARRAY_SIZE(geni_i2c_clk_map); i++, itr++) {
+ if (itr->clk_freq_out == gi2c->clk_freq_out) {
+ gi2c->clk_fld = itr;
+ return 0;
+ }
+ }
+ return -EINVAL;
+}
+
+static void qcom_geni_i2c_conf(struct geni_i2c_dev *gi2c)
+{
+ const struct geni_i2c_clk_fld *itr = gi2c->clk_fld;
+ u32 val;
+
+ writel_relaxed(0, gi2c->se.base + SE_GENI_CLK_SEL);
+
+ val = (itr->clk_div << CLK_DIV_SHFT) | SER_CLK_EN;
+ writel_relaxed(val, gi2c->se.base + GENI_SER_M_CLK_CFG);
+
+ val = itr->t_high_cnt << HIGH_COUNTER_SHFT;
+ val |= itr->t_low_cnt << LOW_COUNTER_SHFT;
+ val |= itr->t_cycle_cnt;
+ writel_relaxed(val, gi2c->se.base + SE_I2C_SCL_COUNTERS);
+}
+
+static void geni_i2c_err_misc(struct geni_i2c_dev *gi2c)
+{
+ u32 m_cmd = readl_relaxed(gi2c->se.base + SE_GENI_M_CMD0);
+ u32 m_stat = readl_relaxed(gi2c->se.base + SE_GENI_M_IRQ_STATUS);
+ u32 geni_s = readl_relaxed(gi2c->se.base + SE_GENI_STATUS);
+ u32 geni_ios = readl_relaxed(gi2c->se.base + SE_GENI_IOS);
+ u32 dma = readl_relaxed(gi2c->se.base + SE_GENI_DMA_MODE_EN);
+ u32 rx_st, tx_st;
+
+ if (dma) {
+ rx_st = readl_relaxed(gi2c->se.base + SE_DMA_RX_IRQ_STAT);
+ tx_st = readl_relaxed(gi2c->se.base + SE_DMA_TX_IRQ_STAT);
+ } else {
+ rx_st = readl_relaxed(gi2c->se.base + SE_GENI_RX_FIFO_STATUS);
+ tx_st = readl_relaxed(gi2c->se.base + SE_GENI_TX_FIFO_STATUS);
+ }
+ dev_dbg(gi2c->se.dev, "DMA:%d tx_stat:0x%x, rx_stat:0x%x, irq-stat:0x%x\n",
+ dma, tx_st, rx_st, m_stat);
+ dev_dbg(gi2c->se.dev, "m_cmd:0x%x, geni_status:0x%x, geni_ios:0x%x\n",
+ m_cmd, geni_s, geni_ios);
+}
+
+static void geni_i2c_err(struct geni_i2c_dev *gi2c, int err)
+{
+ if (!gi2c->err)
+ gi2c->err = gi2c_log[err].err;
+ if (gi2c->cur)
+ dev_dbg(gi2c->se.dev, "len:%d, slv-addr:0x%x, RD/WR:%d\n",
+ gi2c->cur->len, gi2c->cur->addr, gi2c->cur->flags);
+
+ if (err != NACK && err != GENI_ABORT_DONE) {
+ dev_err(gi2c->se.dev, "%s\n", gi2c_log[err].msg);
+ geni_i2c_err_misc(gi2c);
+ }
+}
+
+static irqreturn_t geni_i2c_irq(int irq, void *dev)
+{
+ struct geni_i2c_dev *gi2c = dev;
+ int j;
+ u32 m_stat;
+ u32 rx_st;
+ u32 dm_tx_st;
+ u32 dm_rx_st;
+ u32 dma;
+ struct i2c_msg *cur;
+ unsigned long flags;
+
+ spin_lock_irqsave(&gi2c->lock, flags);
+ m_stat = readl_relaxed(gi2c->se.base + SE_GENI_M_IRQ_STATUS);
+ rx_st = readl_relaxed(gi2c->se.base + SE_GENI_RX_FIFO_STATUS);
+ dm_tx_st = readl_relaxed(gi2c->se.base + SE_DMA_TX_IRQ_STAT);
+ dm_rx_st = readl_relaxed(gi2c->se.base + SE_DMA_RX_IRQ_STAT);
+ dma = readl_relaxed(gi2c->se.base + SE_GENI_DMA_MODE_EN);
+ cur = gi2c->cur;
+
+ if (!cur ||
+ m_stat & (M_CMD_FAILURE_EN | M_CMD_ABORT_EN) ||
+ dm_rx_st & (DM_I2C_CB_ERR)) {
+ if (m_stat & M_GP_IRQ_1_EN)
+ geni_i2c_err(gi2c, NACK);
+ if (m_stat & M_GP_IRQ_3_EN)
+ geni_i2c_err(gi2c, BUS_PROTO);
+ if (m_stat & M_GP_IRQ_4_EN)
+ geni_i2c_err(gi2c, ARB_LOST);
+ if (m_stat & M_CMD_OVERRUN_EN)
+ geni_i2c_err(gi2c, GENI_OVERRUN);
+ if (m_stat & M_ILLEGAL_CMD_EN)
+ geni_i2c_err(gi2c, GENI_ILLEGAL_CMD);
+ if (m_stat & M_CMD_ABORT_EN)
+ geni_i2c_err(gi2c, GENI_ABORT_DONE);
+ if (m_stat & M_GP_IRQ_0_EN)
+ geni_i2c_err(gi2c, GP_IRQ0);
+
+ /* Disable the TX Watermark interrupt to stop TX */
+ if (!dma)
+ writel_relaxed(0, gi2c->se.base +
+ SE_GENI_TX_WATERMARK_REG);
+ goto irqret;
+ }
+
+ if (dma) {
+ dev_dbg(gi2c->se.dev, "i2c dma tx:0x%x, dma rx:0x%x\n",
+ dm_tx_st, dm_rx_st);
+ goto irqret;
+ }
+
+ if (cur->flags & I2C_M_RD &&
+ m_stat & (M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN)) {
+ u32 rxcnt = rx_st & RX_FIFO_WC_MSK;
+
+ for (j = 0; j < rxcnt; j++) {
+ u32 val;
+ int p = 0;
+
+ val = readl_relaxed(gi2c->se.base + SE_GENI_RX_FIFOn);
+ while (gi2c->cur_rd < cur->len && p < sizeof(val)) {
+ cur->buf[gi2c->cur_rd++] = val & 0xff;
+ val >>= 8;
+ p++;
+ }
+ if (gi2c->cur_rd == cur->len)
+ break;
+ }
+ } else if (!(cur->flags & I2C_M_RD) &&
+ m_stat & M_TX_FIFO_WATERMARK_EN) {
+ for (j = 0; j < gi2c->tx_wm; j++) {
+ u32 temp;
+ u32 val = 0;
+ int p = 0;
+
+ while (gi2c->cur_wr < cur->len && p < sizeof(val)) {
+ temp = cur->buf[gi2c->cur_wr++];
+ val |= temp << (p * 8);
+ p++;
+ }
+ writel_relaxed(val, gi2c->se.base + SE_GENI_TX_FIFOn);
+ /* TX Complete, Disable the TX Watermark interrupt */
+ if (gi2c->cur_wr == cur->len) {
+ writel_relaxed(0, gi2c->se.base +
+ SE_GENI_TX_WATERMARK_REG);
+ break;
+ }
+ }
+ }
+irqret:
+ if (m_stat)
+ writel_relaxed(m_stat, gi2c->se.base + SE_GENI_M_IRQ_CLEAR);
+
+ if (dma) {
+ if (dm_tx_st)
+ writel_relaxed(dm_tx_st, gi2c->se.base +
+ SE_DMA_TX_IRQ_CLR);
+ if (dm_rx_st)
+ writel_relaxed(dm_rx_st, gi2c->se.base +
+ SE_DMA_RX_IRQ_CLR);
+ }
+ /* if this is err with done-bit not set, handle that through timeout. */
+ if (m_stat & M_CMD_DONE_EN || m_stat & M_CMD_ABORT_EN)
+ complete(&gi2c->done);
+ else if (dm_tx_st & TX_DMA_DONE || dm_tx_st & TX_RESET_DONE)
+ complete(&gi2c->done);
+ else if (dm_rx_st & RX_DMA_DONE || dm_rx_st & RX_RESET_DONE)
+ complete(&gi2c->done);
+
+ spin_unlock_irqrestore(&gi2c->lock, flags);
+ return IRQ_HANDLED;
+}
+
+static void geni_i2c_abort_xfer(struct geni_i2c_dev *gi2c)
+{
+ u32 val;
+ unsigned long time_left = ABORT_TIMEOUT;
+ unsigned long flags;
+
+ spin_lock_irqsave(&gi2c->lock, flags);
+ geni_i2c_err(gi2c, GENI_TIMEOUT);
+ gi2c->cur = NULL;
+ geni_se_abort_m_cmd(&gi2c->se);
+ spin_unlock_irqrestore(&gi2c->lock, flags);
+ do {
+ time_left = wait_for_completion_timeout(&gi2c->done, time_left);
+ val = readl_relaxed(gi2c->se.base + SE_GENI_M_IRQ_STATUS);
+ } while (!(val & M_CMD_ABORT_EN) && time_left);
+
+ if (!(val & M_CMD_ABORT_EN))
+ dev_err(gi2c->se.dev, "Timeout abort_m_cmd\n");
+}
+
+static void geni_i2c_rx_fsm_rst(struct geni_i2c_dev *gi2c)
+{
+ u32 val;
+ unsigned long time_left = RST_TIMEOUT;
+
+ writel_relaxed(1, gi2c->se.base + SE_DMA_RX_FSM_RST);
+ do {
+ time_left = wait_for_completion_timeout(&gi2c->done, time_left);
+ val = readl_relaxed(gi2c->se.base + SE_DMA_RX_IRQ_STAT);
+ } while (!(val & RX_RESET_DONE) && time_left);
+
+ if (!(val & RX_RESET_DONE))
+ dev_err(gi2c->se.dev, "Timeout resetting RX_FSM\n");
+}
+
+static void geni_i2c_tx_fsm_rst(struct geni_i2c_dev *gi2c)
+{
+ u32 val;
+ unsigned long time_left = RST_TIMEOUT;
+
+ writel_relaxed(1, gi2c->se.base + SE_DMA_TX_FSM_RST);
+ do {
+ time_left = wait_for_completion_timeout(&gi2c->done, time_left);
+ val = readl_relaxed(gi2c->se.base + SE_DMA_TX_IRQ_STAT);
+ } while (!(val & TX_RESET_DONE) && time_left);
+
+ if (!(val & TX_RESET_DONE))
+ dev_err(gi2c->se.dev, "Timeout resetting TX_FSM\n");
+}
+
+static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
+ u32 m_param)
+{
+ dma_addr_t rx_dma;
+ enum geni_se_xfer_mode mode;
+ unsigned long time_left = XFER_TIMEOUT;
+
+ gi2c->cur = msg;
+ mode = msg->len > 32 ? GENI_SE_DMA : GENI_SE_FIFO;
+ geni_se_select_mode(&gi2c->se, mode);
+ writel_relaxed(msg->len, gi2c->se.base + SE_I2C_RX_TRANS_LEN);
+ geni_se_setup_m_cmd(&gi2c->se, I2C_READ, m_param);
+ if (mode == GENI_SE_DMA) {
+ int ret;
+
+ ret = geni_se_rx_dma_prep(&gi2c->se, msg->buf, msg->len,
+ &rx_dma);
+ if (ret) {
+ mode = GENI_SE_FIFO;
+ geni_se_select_mode(&gi2c->se, mode);
+ }
+ }
+
+ time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
+ if (!time_left)
+ geni_i2c_abort_xfer(gi2c);
+
+ gi2c->cur_rd = 0;
+ if (mode == GENI_SE_DMA) {
+ if (gi2c->err)
+ geni_i2c_rx_fsm_rst(gi2c);
+ geni_se_rx_dma_unprep(&gi2c->se, rx_dma, msg->len);
+ }
+ return gi2c->err;
+}
+
+static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
+ u32 m_param)
+{
+ dma_addr_t tx_dma;
+ enum geni_se_xfer_mode mode;
+ unsigned long time_left;
+
+ gi2c->cur = msg;
+ mode = msg->len > 32 ? GENI_SE_DMA : GENI_SE_FIFO;
+ geni_se_select_mode(&gi2c->se, mode);
+ writel_relaxed(msg->len, gi2c->se.base + SE_I2C_TX_TRANS_LEN);
+ geni_se_setup_m_cmd(&gi2c->se, I2C_WRITE, m_param);
+ if (mode == GENI_SE_DMA) {
+ int ret;
+
+ ret = geni_se_tx_dma_prep(&gi2c->se, msg->buf, msg->len,
+ &tx_dma);
+ if (ret) {
+ mode = GENI_SE_FIFO;
+ geni_se_select_mode(&gi2c->se, mode);
+ }
+ }
+
+ if (mode == GENI_SE_FIFO) /* Get FIFO IRQ */
+ writel_relaxed(1, gi2c->se.base + SE_GENI_TX_WATERMARK_REG);
+
+ time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
+ if (!time_left)
+ geni_i2c_abort_xfer(gi2c);
+
+ gi2c->cur_wr = 0;
+ if (mode == GENI_SE_DMA) {
+ if (gi2c->err)
+ geni_i2c_tx_fsm_rst(gi2c);
+ geni_se_tx_dma_unprep(&gi2c->se, tx_dma, msg->len);
+ }
+ return gi2c->err;
+}
+
+static int geni_i2c_xfer(struct i2c_adapter *adap,
+ struct i2c_msg msgs[],
+ int num)
+{
+ struct geni_i2c_dev *gi2c = i2c_get_adapdata(adap);
+ int i, ret;
+
+ gi2c->err = 0;
+ reinit_completion(&gi2c->done);
+ ret = pm_runtime_get_sync(gi2c->se.dev);
+ if (ret < 0) {
+ dev_err(gi2c->se.dev, "error turning SE resources:%d\n", ret);
+ pm_runtime_put_noidle(gi2c->se.dev);
+ /* Set device in suspended since resume failed */
+ pm_runtime_set_suspended(gi2c->se.dev);
+ return ret;
+ }
+
+ qcom_geni_i2c_conf(gi2c);
+ for (i = 0; i < num; i++) {
+ u32 m_param = i < (num - 1) ? STOP_STRETCH : 0;
+
+ m_param |= ((msgs[i].addr << SLV_ADDR_SHFT) & SLV_ADDR_MSK);
+
+ if (msgs[i].flags & I2C_M_RD)
+ ret = geni_i2c_rx_one_msg(gi2c, &msgs[i], m_param);
+ else
+ ret = geni_i2c_tx_one_msg(gi2c, &msgs[i], m_param);
+
+ if (ret)
+ break;
+ }
+ if (ret == 0)
+ ret = num;
+
+ pm_runtime_mark_last_busy(gi2c->se.dev);
+ pm_runtime_put_autosuspend(gi2c->se.dev);
+ gi2c->cur = NULL;
+ gi2c->err = 0;
+ return ret;
+}
+
+static u32 geni_i2c_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+}
+
+static const struct i2c_algorithm geni_i2c_algo = {
+ .master_xfer = geni_i2c_xfer,
+ .functionality = geni_i2c_func,
+};
+
+static int geni_i2c_probe(struct platform_device *pdev)
+{
+ struct geni_i2c_dev *gi2c;
+ struct resource *res;
+ u32 proto, tx_depth;
+ int ret;
+
+ gi2c = devm_kzalloc(&pdev->dev, sizeof(*gi2c), GFP_KERNEL);
+ if (!gi2c)
+ return -ENOMEM;
+
+ gi2c->se.dev = &pdev->dev;
+ gi2c->se.wrapper = dev_get_drvdata(pdev->dev.parent);
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ gi2c->se.base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(gi2c->se.base))
+ return PTR_ERR(gi2c->se.base);
+
+ gi2c->se.clk = devm_clk_get(&pdev->dev, "se");
+ if (IS_ERR(gi2c->se.clk)) {
+ ret = PTR_ERR(gi2c->se.clk);
+ dev_err(&pdev->dev, "Err getting SE Core clk %d\n", ret);
+ return ret;
+ }
+
+ ret = device_property_read_u32(&pdev->dev, "clock-frequency",
+ &gi2c->clk_freq_out);
+ if (ret) {
+ dev_info(&pdev->dev,
+ "Bus frequency not specified, default to 100kHz.\n");
+ gi2c->clk_freq_out = KHZ(100);
+ }
+
+ gi2c->irq = platform_get_irq(pdev, 0);
+ if (gi2c->irq < 0) {
+ dev_err(&pdev->dev, "IRQ error for i2c-geni\n");
+ return gi2c->irq;
+ }
+
+ ret = geni_i2c_clk_map_idx(gi2c);
+ if (ret) {
+ dev_err(&pdev->dev, "Invalid clk frequency %d Hz: %d\n",
+ gi2c->clk_freq_out, ret);
+ return ret;
+ }
+
+ gi2c->adap.algo = &geni_i2c_algo;
+ init_completion(&gi2c->done);
+ spin_lock_init(&gi2c->lock);
+ platform_set_drvdata(pdev, gi2c);
+ ret = devm_request_irq(&pdev->dev, gi2c->irq, geni_i2c_irq,
+ IRQF_TRIGGER_HIGH, "i2c_geni", gi2c);
+ if (ret) {
+ dev_err(&pdev->dev, "Request_irq failed:%d: err:%d\n",
+ gi2c->irq, ret);
+ return ret;
+ }
+ /* Disable the interrupt so that the system can enter low-power mode */
+ disable_irq(gi2c->irq);
+ i2c_set_adapdata(&gi2c->adap, gi2c);
+ gi2c->adap.dev.parent = &pdev->dev;
+ gi2c->adap.dev.of_node = pdev->dev.of_node;
+ strlcpy(gi2c->adap.name, "Geni-I2C", sizeof(gi2c->adap.name));
+
+ ret = geni_se_resources_on(&gi2c->se);
+ if (ret) {
+ dev_err(&pdev->dev, "Error turning on resources %d\n", ret);
+ return ret;
+ }
+ proto = geni_se_read_proto(&gi2c->se);
+ tx_depth = geni_se_get_tx_fifo_depth(&gi2c->se);
+ if (proto != GENI_SE_I2C) {
+ dev_err(&pdev->dev, "Invalid proto %d\n", proto);
+ geni_se_resources_off(&gi2c->se);
+ return -ENXIO;
+ }
+ gi2c->tx_wm = tx_depth - 1;
+ geni_se_init(&gi2c->se, gi2c->tx_wm, tx_depth);
+ geni_se_config_packing(&gi2c->se, BITS_PER_BYTE, PACKING_BYTES_PW,
+ true, true, true);
+ geni_se_resources_off(&gi2c->se);
+ dev_dbg(&pdev->dev, "i2c fifo/se-dma mode. fifo depth:%d\n", tx_depth);
+
+ ret = i2c_add_adapter(&gi2c->adap);
+ if (ret) {
+ dev_err(&pdev->dev, "Error adding i2c adapter %d\n", ret);
+ return ret;
+ }
+ pm_runtime_set_suspended(gi2c->se.dev);
+ pm_runtime_set_autosuspend_delay(gi2c->se.dev, I2C_AUTO_SUSPEND_DELAY);
+ pm_runtime_use_autosuspend(gi2c->se.dev);
+ pm_runtime_enable(gi2c->se.dev);
+
+ return 0;
+}
+
+static int geni_i2c_remove(struct platform_device *pdev)
+{
+ struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev);
+
+ pm_runtime_disable(gi2c->se.dev);
+ i2c_del_adapter(&gi2c->adap);
+ return 0;
+}
+
+static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev)
+{
+ struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
+
+ disable_irq(gi2c->irq);
+ geni_se_resources_off(&gi2c->se);
+ return 0;
+}
+
+static int __maybe_unused geni_i2c_runtime_resume(struct device *dev)
+{
+ int ret;
+ struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
+
+ ret = geni_se_resources_on(&gi2c->se);
+ if (ret)
+ return ret;
+
+ enable_irq(gi2c->irq);
+ return 0;
+}
+
+static int __maybe_unused geni_i2c_suspend_noirq(struct device *dev)
+{
+ if (!pm_runtime_suspended(dev)) {
+ geni_i2c_runtime_suspend(dev);
+ pm_runtime_disable(dev);
+ pm_runtime_set_suspended(dev);
+ pm_runtime_enable(dev);
+ }
+ return 0;
+}
+
+static const struct dev_pm_ops geni_i2c_pm_ops = {
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(geni_i2c_suspend_noirq, NULL)
+ SET_RUNTIME_PM_OPS(geni_i2c_runtime_suspend, geni_i2c_runtime_resume,
+ NULL)
+};
+
+static const struct of_device_id geni_i2c_dt_match[] = {
+ { .compatible = "qcom,geni-i2c" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, geni_i2c_dt_match);
+
+static struct platform_driver geni_i2c_driver = {
+ .probe = geni_i2c_probe,
+ .remove = geni_i2c_remove,
+ .driver = {
+ .name = "geni_i2c",
+ .pm = &geni_i2c_pm_ops,
+ .of_match_table = geni_i2c_dt_match,
+ },
+};
+
+module_platform_driver(geni_i2c_driver);
+
+MODULE_DESCRIPTION("I2C Controller Driver for GENI based QUP cores");
+MODULE_LICENSE("GPL v2");
--
Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project