[PATCH v3 i2c-master] i2c: microchip: pci1xxxx: Add driver for I2C host controller in multifunction endpoint of pci1xxxx switch
From: Tharun Kumar P
Date: Tue Sep 06 2022 - 06:20:31 EST
Microchip pci1xxxx is an unmanaged PCIe3.1a Switch for Consumer,
Industrial and Automotive applications. This switch has multiple
downstream ports. In one of the Switch's Downstream port, there
is a multifunction endpoint for peripherals which includes an I2C
host controller. The I2C function in the endpoint operates at 100KHz,
400KHz and 1 MHz and has buffer depth of 128 bytes.
This patch provides the I2C controller driver for the I2C function
of the switch.
Signed-off-by: Tharun Kumar P <tharunkumar.pasumarthi@xxxxxxxxxxxxx>
---
V2 -> V3:
1. Replaced SIMPLE_DEV_PM_OPS with DEFINE_SIMPLE_DEV_PM_OPS
2. Used devm_add_action API to avoid mixing devm and non-devm APIs
---
RFC -> V2:
1. Removed pci_free_irq_vectors API in code since pcim_enable_device
is used
2. Added pci1xxxx_i2c_shutdown API in failure case of
pci_alloc_irq_vectors and devm_request_irq
3. Used devm variant of i2c_add_adapter
4. Resolved name collision and fixed styling issues in comments
---
MAINTAINERS | 8 +
drivers/i2c/busses/Kconfig | 10 +
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-mchp-pci1xxxx.c | 1227 ++++++++++++++++++++++++
4 files changed, 1246 insertions(+)
create mode 100644 drivers/i2c/busses/i2c-mchp-pci1xxxx.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 3cf9842d9233..204885ab5200 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -13110,6 +13110,14 @@ S: Supported
F: Documentation/devicetree/bindings/mtd/atmel-nand.txt
F: drivers/mtd/nand/raw/atmel/*
+MICROCHIP PCI1XXXX I2C DRIVER
+M: Tharun Kumar P <tharunkumar.pasumarthi@xxxxxxxxxxxxx>
+M: Kumaravel Thiagarajan <kumaravel.thiagarajan@xxxxxxxxxxxxx>
+M: Microchip Linux Driver Support <UNGLinuxDriver@xxxxxxxxxxxxx>
+L: linux-i2c@xxxxxxxxxxxxxxx
+S: Maintained
+F: drivers/i2c/busses/i2c-mchp-pci1xxxx.c
+
MICROCHIP PWM DRIVER
M: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
L: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx (moderated for non-subscribers)
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index a1bae59208e3..7e967d87dc04 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -1244,6 +1244,16 @@ config I2C_PARPORT
This support is also available as a module. If so, the module
will be called i2c-parport.
+config I2C_PCI1XXXX
+ tristate "PCI1XXXX I2C Host Adapter"
+ depends on PCI
+ help
+ If you say yes to this option, support will be included for
+ Microchip PCI1XXXX's I2C interface.
+
+ This driver can also be built as a module. If so, the module will
+ be called i2c-mchp-pci1xxxx.
+
config I2C_ROBOTFUZZ_OSIF
tristate "RobotFuzz Open Source InterFace USB adapter"
depends on USB
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 479f60e4ee3d..2372ed91e7ad 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -131,6 +131,7 @@ obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o
obj-$(CONFIG_I2C_DLN2) += i2c-dln2.o
obj-$(CONFIG_I2C_CP2615) += i2c-cp2615.o
obj-$(CONFIG_I2C_PARPORT) += i2c-parport.o
+obj-$(CONFIG_I2C_PCI1XXXX) += i2c-mchp-pci1xxxx.o
obj-$(CONFIG_I2C_ROBOTFUZZ_OSIF) += i2c-robotfuzz-osif.o
obj-$(CONFIG_I2C_TAOS_EVM) += i2c-taos-evm.o
obj-$(CONFIG_I2C_TINY_USB) += i2c-tiny-usb.o
diff --git a/drivers/i2c/busses/i2c-mchp-pci1xxxx.c b/drivers/i2c/busses/i2c-mchp-pci1xxxx.c
new file mode 100644
index 000000000000..ef7a25499831
--- /dev/null
+++ b/drivers/i2c/busses/i2c-mchp-pci1xxxx.c
@@ -0,0 +1,1227 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Microchip PCI1XXXX I2C adapter driver for PCIe Switch
+ * which has I2C controller in one of its downstream functions
+ *
+ * Copyright (C) 2021 - 2022 Microchip Technology Inc.
+ *
+ * Authors: Tharun Kumar P <tharunkumar.pasumarthi@xxxxxxxxxxxxx>
+ * Kumaravel Thiagarajan <kumaravel.thiagarajan@xxxxxxxxxxxxx>
+ */
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/i2c-smbus.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+
+#define SMBUS_MAST_CORE_ADDR_BASE 0x00000
+#define SMBUS_MAST_SYS_REG_ADDR_BASE 0x01000
+
+#define PCI1XXXX_IRQ_FLAGS 0
+
+/* SMB register space. */
+#define SMB_CORE_CTRL_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x00)
+
+#define SMB_CORE_CTRL_ESO BIT(6)
+#define SMB_CORE_CTRL_FW_ACK BIT(4)
+
+#define SMB_CORE_CMD_REG_OFF3 (SMBUS_MAST_CORE_ADDR_BASE + 0x0F)
+#define SMB_CORE_CMD_REG_OFF2 (SMBUS_MAST_CORE_ADDR_BASE + 0x0E)
+#define SMB_CORE_CMD_REG_OFF1 (SMBUS_MAST_CORE_ADDR_BASE + 0x0D)
+
+#define SMB_CORE_CMD_READM BIT(4)
+#define SMB_CORE_CMD_STOP BIT(2)
+#define SMB_CORE_CMD_START BIT(0)
+
+#define SMB_CORE_CMD_REG_OFF0 (SMBUS_MAST_CORE_ADDR_BASE + 0x0C)
+
+#define SMB_CORE_CMD_M_PROCEED BIT(1)
+#define SMB_CORE_CMD_M_RUN BIT(0)
+
+#define SMB_CORE_SR_HOLD_TIME_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x18)
+
+/*
+ * SR_HOLD_TIME_XK_TICKS field will indicate the number of ticks of the
+ * baud clock required to program 'Hold Time' at X KHz.
+ */
+#define SR_HOLD_TIME_100K_TICKS 133
+#define SR_HOLD_TIME_400K_TICKS 20
+#define SR_HOLD_TIME_1000K_TICKS 11
+
+#define SMB_CORE_COMPLETION_REG_OFF3 (SMBUS_MAST_CORE_ADDR_BASE + 0x23)
+
+#define COMPLETION_MDONE BIT(6)
+#define COMPLETION_IDLE BIT(5)
+#define COMPLETION_MNAKX BIT(0)
+
+#define SMB_CORE_IDLE_SCALING_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x24)
+
+/*
+ * FAIR_BUS_IDLE_MIN_XK_TICKS field will indicate the number of ticks of
+ * the baud clock required to program 'fair idle delay' at X KHz. Fair idle
+ * delay establishes the MCTP T(IDLE_DELAY) period.
+ */
+#define FAIR_BUS_IDLE_MIN_100K_TICKS 969
+#define FAIR_BUS_IDLE_MIN_400K_TICKS 157
+#define FAIR_BUS_IDLE_MIN_1000K_TICKS 157
+
+/*
+ * FAIR_IDLE_DELAY_XK_TICKS field will indicate the number of ticks of the
+ * baud clock required to satisfy the fairness protocol at X KHz.
+ */
+#define FAIR_IDLE_DELAY_100K_TICKS 1000
+#define FAIR_IDLE_DELAY_400K_TICKS 500
+#define FAIR_IDLE_DELAY_1000K_TICKS 500
+
+#define SMB_IDLE_SCALING_100K \
+ ((FAIR_IDLE_DELAY_100K_TICKS << 16) | FAIR_BUS_IDLE_MIN_100K_TICKS)
+#define SMB_IDLE_SCALING_400K \
+ ((FAIR_IDLE_DELAY_400K_TICKS << 16) | FAIR_BUS_IDLE_MIN_400K_TICKS)
+#define SMB_IDLE_SCALING_1000K \
+ ((FAIR_IDLE_DELAY_1000K_TICKS << 16) | FAIR_BUS_IDLE_MIN_1000K_TICKS)
+
+#define SMB_CORE_CONFIG_REG3 (SMBUS_MAST_CORE_ADDR_BASE + 0x2B)
+
+#define SMB_CONFIG3_ENMI BIT(6)
+#define SMB_CONFIG3_ENIDI BIT(5)
+
+#define SMB_CORE_CONFIG_REG2 (SMBUS_MAST_CORE_ADDR_BASE + 0x2A)
+#define SMB_CORE_CONFIG_REG1 (SMBUS_MAST_CORE_ADDR_BASE + 0x29)
+
+#define SMB_CONFIG1_ASR BIT(7)
+#define SMB_CONFIG1_ENAB BIT(2)
+#define SMB_CONFIG1_RESET BIT(1)
+#define SMB_CONFIG1_FEN BIT(0)
+
+#define SMB_CORE_BUS_CLK_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x2C)
+
+/*
+ * BUS_CLK_XK_LOW_PERIOD_TICKS field defines the number of I2C Baud Clock
+ * periods that make up the low phase of the I2C/SMBus bus clock at X KHz.
+ */
+#define BUS_CLK_100K_LOW_PERIOD_TICKS 156
+#define BUS_CLK_400K_LOW_PERIOD_TICKS 41
+#define BUS_CLK_1000K_LOW_PERIOD_TICKS 15
+
+/*
+ * BUS_CLK_XK_HIGH_PERIOD_TICKS field defines the number of I2C Baud Clock
+ * periods that make up the high phase of the I2C/SMBus bus clock at X KHz.
+ */
+#define BUS_CLK_100K_HIGH_PERIOD_TICKS 154
+#define BUS_CLK_400K_HIGH_PERIOD_TICKS 35
+#define BUS_CLK_1000K_HIGH_PERIOD_TICKS 14
+
+#define BUS_CLK_100K \
+ ((BUS_CLK_100K_HIGH_PERIOD_TICKS << 8) | BUS_CLK_100K_LOW_PERIOD_TICKS)
+#define BUS_CLK_400K \
+ ((BUS_CLK_400K_HIGH_PERIOD_TICKS << 8) | BUS_CLK_400K_LOW_PERIOD_TICKS)
+#define BUS_CLK_1000K \
+ ((BUS_CLK_1000K_HIGH_PERIOD_TICKS << 8) | BUS_CLK_1000K_LOW_PERIOD_TICKS)
+
+#define SMB_CORE_CLK_SYNC_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x3C)
+
+/*
+ * CLK_SYNC_XK defines the number of clock cycles to sync up to the external
+ * clock before comparing the internal and external clocks for clock stretching
+ * at X KHz.
+ */
+#define CLK_SYNC_100K 4
+#define CLK_SYNC_400K 4
+#define CLK_SYNC_1000K 4
+
+#define SMB_CORE_DATA_TIMING_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x40)
+
+/*
+ *
+ * FIRST_START_HOLD_XK_TICKS will indicate the number of ticks of the baud
+ * clock required to program 'FIRST_START_HOLD' timer at X KHz. This timer
+ * determines the SCLK hold time following SDAT driven low during the first
+ * START bit in a transfer.
+ */
+#define FIRST_START_HOLD_100K_TICKS 22
+#define FIRST_START_HOLD_400K_TICKS 16
+#define FIRST_START_HOLD_1000K_TICKS 6
+
+/*
+ * STOP_SETUP_XK_TICKS will indicate the number of ticks of the baud clock
+ * required to program 'STOP_SETUP' timer at X KHz. This timer determines the
+ * SDAT setup time from the rising edge of SCLK for a STOP condition.
+ */
+#define STOP_SETUP_100K_TICKS 157
+#define STOP_SETUP_400K_TICKS 20
+#define STOP_SETUP_1000K_TICKS 12
+
+/*
+ * RESTART_SETUP_XK_TICKS will indicate the number of ticks of the baud clock
+ * required to program 'RESTART_SETUP' timer at X KHz. This timer determines the
+ * SDAT setup time from the rising edge of SCLK for a repeated START condition.
+ */
+#define RESTART_SETUP_100K_TICKS 157
+#define RESTART_SETUP_400K_TICKS 20
+#define RESTART_SETUP_1000K_TICKS 12
+
+/*
+ * DATA_HOLD_XK_TICKS will indicate the number of ticks of the baud clock
+ * required to program 'DATA_HOLD' timer at X KHz. This timer determines the
+ * SDAT hold time following SCLK driven low.
+ */
+#define DATA_HOLD_100K_TICKS 2
+#define DATA_HOLD_400K_TICKS 2
+#define DATA_HOLD_1000K_TICKS 2
+
+#define DATA_TIMING_100K \
+ ((FIRST_START_HOLD_100K_TICKS << 24) | (STOP_SETUP_100K_TICKS << 16) | \
+ (RESTART_SETUP_100K_TICKS << 8) | DATA_HOLD_100K_TICKS)
+#define DATA_TIMING_400K \
+ ((FIRST_START_HOLD_400K_TICKS << 24) | (STOP_SETUP_400K_TICKS << 16) | \
+ (RESTART_SETUP_400K_TICKS << 8) | DATA_HOLD_400K_TICKS)
+#define DATA_TIMING_1000K \
+ ((FIRST_START_HOLD_1000K_TICKS << 24) | (STOP_SETUP_1000K_TICKS << 16) | \
+ (RESTART_SETUP_1000K_TICKS << 8) | DATA_HOLD_1000K_TICKS)
+
+#define SMB_CORE_TO_SCALING_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x44)
+
+/*
+ * BUS_IDLE_MIN_XK_TICKS defines Bus Idle Minimum Time.
+ * Bus Idle Minimum time = BUS_IDLE_MIN[7:0] x Baud_Clock_Period x
+ * (BUS_IDLE_MIN_XK_TICKS[7] ? 4,1)
+ */
+#define BUS_IDLE_MIN_100K_TICKS 167
+#define BUS_IDLE_MIN_400K_TICKS 139
+#define BUS_IDLE_MIN_1000K_TICKS 133
+
+/*
+ * CTRL_CUM_TIME_OUT_XK_TICKS defines SMBus Controller Cumulative Time-Out.
+ * SMBus Controller Cumulative Time-Out duration =
+ * CTRL_CUM_TIME_OUT_XK_TICKS[7:0] x Baud_Clock_Period x 2048
+ */
+#define CTRL_CUM_TIME_OUT_100K_TICKS 159
+#define CTRL_CUM_TIME_OUT_400K_TICKS 159
+#define CTRL_CUM_TIME_OUT_1000K_TICKS 159
+
+/*
+ * TARGET_CUM_TIME_OUT_XK_TICKS defines SMBus Target Cumulative Time-Out duration.
+ * SMBus Target Cumulative Time-Out duration = TARGET_CUM_TIME_OUT_XK_TICKS[7:0] x
+ * Baud_Clock_Period x 4096
+ */
+#define TARGET_CUM_TIME_OUT_100K_TICKS 199
+#define TARGET_CUM_TIME_OUT_400K_TICKS 199
+#define TARGET_CUM_TIME_OUT_1000K_TICKS 199
+
+/*
+ * CLOCK_HIGH_TIME_OUT_XK defines Clock High time out period.
+ * Clock High time out period = CLOCK_HIGH_TIME_OUT_XK[7:0] x Baud_Clock_Period x 8
+ */
+#define CLOCK_HIGH_TIME_OUT_100K_TICKS 204
+#define CLOCK_HIGH_TIME_OUT_400K_TICKS 204
+#define CLOCK_HIGH_TIME_OUT_1000K_TICKS 204
+
+#define TO_SCALING_100K \
+ ((BUS_IDLE_MIN_100K_TICKS << 24) | (CTRL_CUM_TIME_OUT_100K_TICKS << 16) | \
+ (TARGET_CUM_TIME_OUT_100K_TICKS << 8) | CLOCK_HIGH_TIME_OUT_100K_TICKS)
+#define TO_SCALING_400K \
+ ((BUS_IDLE_MIN_400K_TICKS << 24) | (CTRL_CUM_TIME_OUT_400K_TICKS << 16) | \
+ (TARGET_CUM_TIME_OUT_400K_TICKS << 8) | CLOCK_HIGH_TIME_OUT_400K_TICKS)
+#define TO_SCALING_1000K \
+ ((BUS_IDLE_MIN_1000K_TICKS << 24) | (CTRL_CUM_TIME_OUT_1000K_TICKS << 16) | \
+ (TARGET_CUM_TIME_OUT_1000K_TICKS << 8) | CLOCK_HIGH_TIME_OUT_1000K_TICKS)
+
+#define I2C_SCL_PAD_CTRL_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x100)
+#define I2C_SDA_PAD_CTRL_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x101)
+
+#define I2C_FOD_EN BIT(4)
+#define I2C_PULL_UP_EN BIT(3)
+#define I2C_PULL_DOWN_EN BIT(2)
+#define I2C_INPUT_EN BIT(1)
+#define I2C_OUTPUT_EN BIT(0)
+
+#define SMBUS_CONTROL_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x200)
+
+#define CTL_RESET_COUNTERS BIT(3)
+#define CTL_TRANSFER_DIR BIT(2)
+#define CTL_HOST_FIFO_ENTRY BIT(1)
+#define CTL_RUN BIT(0)
+
+#define I2C_DIRN_WRITE 0
+#define I2C_DIRN_READ 1
+
+#define SMBUS_STATUS_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x204)
+
+#define STA_DMA_TERM BIT(7)
+#define STA_DMA_REQ BIT(6)
+#define STA_THRESHOLD BIT(2)
+#define STA_BUF_FULL BIT(1)
+#define STA_BUF_EMPTY BIT(0)
+
+#define SMBUS_INTR_STAT_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x208)
+
+#define INTR_STAT_DMA_TERM BIT(7)
+#define INTR_STAT_THRESHOLD BIT(2)
+#define INTR_STAT_BUF_FULL BIT(1)
+#define INTR_STAT_BUF_EMPTY BIT(0)
+
+#define SMBUS_INTR_MSK_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x20C)
+
+#define INTR_MSK_DMA_TERM BIT(7)
+#define INTR_MSK_THRESHOLD BIT(2)
+#define INTR_MSK_BUF_FULL BIT(1)
+#define INTR_MSK_BUF_EMPTY BIT(0)
+
+#define ALL_NW_LAYER_INTERRUPTS \
+ (INTR_MSK_DMA_TERM | INTR_MSK_THRESHOLD | INTR_MSK_BUF_FULL | \
+ INTR_MSK_BUF_EMPTY)
+
+#define SMBUS_MCU_COUNTER_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x214)
+
+#define SMBALERT_MST_PAD_CTRL_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x230)
+
+#define SMBALERT_MST_PU BIT(0)
+
+#define SMBUS_GEN_INT_STAT_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x23C)
+
+#define SMBUS_GEN_INT_MASK_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x240)
+
+#define SMBALERT_INTR_MASK BIT(10)
+#define I2C_BUF_MSTR_INTR_MASK BIT(9)
+#define I2C_INTR_MASK BIT(8)
+#define SMBALERT_WAKE_INTR_MASK BIT(2)
+#define I2C_BUF_MSTR_WAKE_INTR_MASK BIT(1)
+#define I2C_WAKE_INTR_MASK BIT(0)
+
+#define ALL_HIGH_LAYER_INTR \
+ (SMBALERT_INTR_MASK | I2C_BUF_MSTR_INTR_MASK | I2C_INTR_MASK | \
+ SMBALERT_WAKE_INTR_MASK | I2C_BUF_MSTR_WAKE_INTR_MASK | \
+ I2C_WAKE_INTR_MASK)
+
+#define SMBUS_RESET_REG (SMBUS_MAST_CORE_ADDR_BASE + 0x248)
+
+#define PERI_SMBUS_D3_RESET_DIS BIT(16)
+
+#define SMBUS_MST_BUF (SMBUS_MAST_CORE_ADDR_BASE + 0x280)
+
+#define SMBUS_BUF_MAX_SIZE 0x80
+
+#define I2C_FLAGS_DIRECT_MODE BIT(7)
+#define I2C_FLAGS_POLLING_MODE BIT(6)
+#define I2C_FLAGS_STOP BIT(5)
+#define I2C_FLAGS_SMB_BLK_READ BIT(4)
+
+#define PCI1XXXX_I2C_TIMEOUT_MS 1000
+
+/* General Purpose Register. */
+#define SMB_GPR_REG (SMBUS_MAST_CORE_ADDR_BASE + 0x1000 + 0x0c00 + \
+ 0x00)
+
+/* Lock Register. */
+#define SMB_GPR_LOCK_REG (SMBUS_MAST_CORE_ADDR_BASE + 0x1000 + 0x0000 + \
+ 0x00A0)
+
+#define SMBUS_PERI_LOCK BIT(3)
+
+struct pci1xxxx_i2c {
+ struct completion i2c_xfer_done;
+ bool i2c_xfer_in_progress;
+ struct i2c_adapter adap;
+ void __iomem *i2c_base;
+ u32 freq;
+ u32 flags;
+};
+
+static int set_sys_lock(struct pci1xxxx_i2c *i2c)
+{
+ void __iomem *bp;
+ u8 data;
+
+ bp = i2c->i2c_base;
+ writel(SMBUS_PERI_LOCK, bp + SMB_GPR_LOCK_REG);
+ data = readl(bp + SMB_GPR_LOCK_REG);
+ if (data != SMBUS_PERI_LOCK)
+ return -EPERM;
+
+ return 0;
+}
+
+static int release_sys_lock(struct pci1xxxx_i2c *i2c)
+{
+ void __iomem *bp;
+ u8 data;
+
+ bp = i2c->i2c_base;
+ data = readl(bp + SMB_GPR_LOCK_REG);
+ if (data != SMBUS_PERI_LOCK)
+ return 0;
+
+ writel(0, bp + SMB_GPR_LOCK_REG);
+ data = readl(bp + SMB_GPR_LOCK_REG);
+ if (data & SMBUS_PERI_LOCK)
+ return -EPERM;
+
+ return 0;
+}
+
+static void pci1xxxx_ack_high_level_intr(struct pci1xxxx_i2c *i2c, u16 intr_msk)
+{
+ writew(intr_msk, i2c->i2c_base + SMBUS_GEN_INT_STAT_REG_OFF);
+}
+
+static void pci1xxxx_i2c_configure_smbalert_pin(struct pci1xxxx_i2c *i2c,
+ bool enable)
+{
+ void __iomem *bp;
+ u8 regval;
+
+ bp = i2c->i2c_base;
+ regval = readb(bp + SMBALERT_MST_PAD_CTRL_REG_OFF);
+
+ if (enable)
+ regval |= SMBALERT_MST_PU;
+ else
+ regval &= ~SMBALERT_MST_PU;
+
+ writeb(regval, bp + SMBALERT_MST_PAD_CTRL_REG_OFF);
+}
+
+static void pci1xxxx_i2c_send_start_stop(struct pci1xxxx_i2c *i2c, bool start)
+{
+ void __iomem *bp;
+ u8 regval;
+
+ bp = i2c->i2c_base;
+ regval = readb(bp + SMB_CORE_CMD_REG_OFF1);
+
+ if (start)
+ regval |= SMB_CORE_CMD_START;
+ else
+ regval |= SMB_CORE_CMD_STOP;
+
+ writeb(regval, bp + SMB_CORE_CMD_REG_OFF1);
+}
+
+/*
+ * When accessing the core control reg, we should not do a read modified write
+ * as they are write '1' to clear bits. Instead we need to write with the
+ * specific bits that needs to be set.
+ */
+static void pci1xxxx_i2c_set_clear_FW_ACK(struct pci1xxxx_i2c *i2c, bool set)
+{
+ u8 regval;
+
+ if (set)
+ regval = SMB_CORE_CTRL_FW_ACK | SMB_CORE_CTRL_ESO;
+ else
+ regval = SMB_CORE_CTRL_ESO;
+
+ writeb(regval, i2c->i2c_base + SMB_CORE_CTRL_REG_OFF);
+}
+
+static void pci1xxxx_i2c_buffer_write(struct pci1xxxx_i2c *i2c, u8 slaveaddr,
+ u8 transferlen, unsigned char *buf)
+{
+ void __iomem *bp;
+
+ bp = i2c->i2c_base;
+ if (slaveaddr) {
+ writeb(slaveaddr, bp + SMBUS_MST_BUF);
+ if (buf)
+ memcpy_toio(bp + SMBUS_MST_BUF + 1, buf, transferlen);
+ } else {
+ if (buf)
+ memcpy_toio(bp + SMBUS_MST_BUF, buf, transferlen);
+ }
+}
+
+/*
+ * When accessing the core control reg, we should not do a read modified write
+ * as there are write '1' to clear bits. Instead we need to write with the
+ * specific bits that needs to be set.
+ */
+static void pci1xxxx_i2c_enable_ESO(struct pci1xxxx_i2c *i2c)
+{
+ writeb(SMB_CORE_CTRL_ESO, i2c->i2c_base + SMB_CORE_CTRL_REG_OFF);
+}
+
+static void pci1xxxx_i2c_reset_counters(struct pci1xxxx_i2c *i2c)
+{
+ void __iomem *bp;
+ u8 regval;
+
+ bp = i2c->i2c_base;
+ regval = readb(bp + SMBUS_CONTROL_REG_OFF);
+ regval |= CTL_RESET_COUNTERS;
+ writeb(regval, bp + SMBUS_CONTROL_REG_OFF);
+}
+
+static void pci1xxxx_i2c_set_transfer_dir(struct pci1xxxx_i2c *i2c, u8 direction)
+{
+ void __iomem *bp;
+ u8 regval;
+
+ bp = i2c->i2c_base;
+ regval = readb(bp + SMBUS_CONTROL_REG_OFF);
+ if (direction == I2C_DIRN_WRITE)
+ regval &= ~CTL_TRANSFER_DIR;
+ else
+ regval |= CTL_TRANSFER_DIR;
+
+ writeb(regval, bp + SMBUS_CONTROL_REG_OFF);
+}
+
+static void pci1xxxx_i2c_set_mcu_count(struct pci1xxxx_i2c *i2c, u8 count)
+{
+ writeb(count, i2c->i2c_base + SMBUS_MCU_COUNTER_REG_OFF);
+}
+
+static void pci1xxxx_i2c_set_read_count(struct pci1xxxx_i2c *i2c, u8 readcount)
+{
+ writeb(readcount, i2c->i2c_base + SMB_CORE_CMD_REG_OFF3);
+}
+
+static void pci1xxxx_i2c_set_write_count(struct pci1xxxx_i2c *i2c, u8 writecount)
+{
+ writeb(writecount, i2c->i2c_base + SMB_CORE_CMD_REG_OFF2);
+}
+
+static void pci1xxxx_i2c_set_DMA_run(struct pci1xxxx_i2c *i2c)
+{
+ void __iomem *bp;
+ u8 regval;
+
+ bp = i2c->i2c_base;
+ regval = readb(bp + SMBUS_CONTROL_REG_OFF);
+ regval |= CTL_RUN;
+ writeb(regval, bp + SMBUS_CONTROL_REG_OFF);
+}
+
+static void pci1xxxx_i2c_set_mrun_proceed(struct pci1xxxx_i2c *i2c)
+{
+ void __iomem *bp;
+ u8 regval;
+
+ bp = i2c->i2c_base;
+ regval = readb(bp + SMB_CORE_CMD_REG_OFF0);
+ regval |= SMB_CORE_CMD_M_RUN;
+ regval |= SMB_CORE_CMD_M_PROCEED;
+ writeb(regval, bp + SMB_CORE_CMD_REG_OFF0);
+}
+
+static void pci1xxxx_i2c_start_DMA(struct pci1xxxx_i2c *i2c)
+{
+ pci1xxxx_i2c_set_DMA_run(i2c);
+ pci1xxxx_i2c_set_mrun_proceed(i2c);
+}
+
+static void pci1xxxx_i2c_config_asr(struct pci1xxxx_i2c *i2c, bool enable)
+{
+ void __iomem *bp;
+ u8 regval;
+
+ bp = i2c->i2c_base;
+ regval = readb(bp + SMB_CORE_CONFIG_REG1);
+ if (enable)
+ regval |= SMB_CONFIG1_ASR;
+ else
+ regval &= ~SMB_CONFIG1_ASR;
+ writeb(regval, bp + SMB_CORE_CONFIG_REG1);
+}
+
+static irqreturn_t pci1xxxx_i2c_isr(int irq, void *dev)
+{
+ irqreturn_t intr_handled = IRQ_NONE;
+ struct pci1xxxx_i2c *i2c = dev;
+ void __iomem *bp;
+ u16 reg1;
+ u8 reg3;
+
+ bp = i2c->i2c_base;
+
+ /*
+ * Read the SMBus interrupt status register to see if the
+ * DMA_TERM interrupt has caused this callback.
+ */
+ reg1 = readw(bp + SMBUS_GEN_INT_STAT_REG_OFF);
+
+ if (reg1 & I2C_BUF_MSTR_INTR_MASK) {
+ reg3 = readb(bp + SMBUS_INTR_STAT_REG_OFF);
+ if (reg3 & INTR_STAT_DMA_TERM) {
+ complete(&i2c->i2c_xfer_done);
+ intr_handled = IRQ_HANDLED;
+ writeb(INTR_STAT_DMA_TERM, bp + SMBUS_INTR_STAT_REG_OFF);
+ }
+ pci1xxxx_ack_high_level_intr(i2c, I2C_BUF_MSTR_INTR_MASK);
+ }
+
+ if (reg1 & SMBALERT_INTR_MASK) {
+ intr_handled = IRQ_HANDLED;
+ pci1xxxx_ack_high_level_intr(i2c, SMBALERT_INTR_MASK);
+ }
+
+ return intr_handled;
+}
+
+static void pci1xxxx_i2c_set_count(struct pci1xxxx_i2c *i2c, u8 mcucount,
+ u8 writecount, u8 readcount)
+{
+ pci1xxxx_i2c_set_mcu_count(i2c, mcucount);
+ pci1xxxx_i2c_set_write_count(i2c, writecount);
+ pci1xxxx_i2c_set_read_count(i2c, readcount);
+}
+
+static void pci1xxxx_i2c_set_readm(struct pci1xxxx_i2c *i2c, bool enable)
+{
+ void __iomem *bp;
+ u8 regval;
+
+ bp = i2c->i2c_base;
+ regval = readb(bp + SMB_CORE_CMD_REG_OFF1);
+ if (enable)
+ regval |= SMB_CORE_CMD_READM;
+ else
+ regval &= ~SMB_CORE_CMD_READM;
+
+ writeb(regval, bp + SMB_CORE_CMD_REG_OFF1);
+}
+
+static void pci1xxxx_ack_nw_layer_intr(struct pci1xxxx_i2c *i2c, u8 ack_intr_msk)
+{
+ writeb(ack_intr_msk, i2c->i2c_base + SMBUS_INTR_STAT_REG_OFF);
+}
+
+static void pci1xxxx_config_nw_layer_intr(struct pci1xxxx_i2c *i2c,
+ u8 intr_msk, bool enable)
+{
+ void __iomem *bp;
+ u8 regval;
+
+ bp = i2c->i2c_base;
+ regval = readb(bp + SMBUS_INTR_MSK_REG_OFF);
+ if (enable)
+ regval &= ~intr_msk;
+ else
+ regval |= intr_msk;
+
+ writeb(regval, bp + SMBUS_INTR_MSK_REG_OFF);
+}
+
+static void pci1xxxx_i2c_config_padctrl(struct pci1xxxx_i2c *i2c, bool enable)
+{
+ void __iomem *bp;
+ u8 regval;
+
+ bp = i2c->i2c_base;
+ regval = readb(bp + I2C_SCL_PAD_CTRL_REG_OFF);
+ if (enable)
+ regval |= I2C_INPUT_EN | I2C_OUTPUT_EN;
+ else
+ regval &= ~(I2C_INPUT_EN | I2C_OUTPUT_EN);
+
+ writeb(regval, bp + I2C_SCL_PAD_CTRL_REG_OFF);
+
+ regval = readb(bp + I2C_SDA_PAD_CTRL_REG_OFF);
+ if (enable)
+ regval |= I2C_INPUT_EN | I2C_OUTPUT_EN;
+ else
+ regval &= ~(I2C_INPUT_EN | I2C_OUTPUT_EN);
+
+ writeb(regval, bp + I2C_SDA_PAD_CTRL_REG_OFF);
+}
+
+static void pci1xxxx_i2c_set_mode(struct pci1xxxx_i2c *i2c)
+{
+ void __iomem *bp;
+ u8 regval;
+
+ bp = i2c->i2c_base;
+ regval = readb(bp + SMBUS_CONTROL_REG_OFF);
+ if (i2c->flags & I2C_FLAGS_DIRECT_MODE)
+ regval &= ~CTL_HOST_FIFO_ENTRY;
+ else
+ regval |= CTL_HOST_FIFO_ENTRY;
+
+ writeb(regval, bp + SMBUS_CONTROL_REG_OFF);
+}
+
+static void pci1xxxx_i2c_config_high_level_intr(struct pci1xxxx_i2c *i2c,
+ u16 intr_msk, bool enable)
+{
+ void __iomem *bp;
+ u16 regval;
+
+ bp = i2c->i2c_base;
+ regval = readw(bp + SMBUS_GEN_INT_MASK_REG_OFF);
+ if (enable)
+ regval &= ~intr_msk;
+ else
+ regval |= intr_msk;
+ writew(regval, bp + SMBUS_GEN_INT_MASK_REG_OFF);
+}
+
+static void pci1xxxx_i2c_configure_core_reg(struct pci1xxxx_i2c *i2c, bool enable)
+{
+ void __iomem *bp;
+ u8 reg1;
+ u8 reg3;
+
+ bp = i2c->i2c_base;
+ reg1 = readb(bp + SMB_CORE_CONFIG_REG1);
+ reg3 = readb(bp + SMB_CORE_CONFIG_REG3);
+ if (enable) {
+ reg1 |= SMB_CONFIG1_ENAB | SMB_CONFIG1_FEN;
+ reg3 |= SMB_CONFIG3_ENMI | SMB_CONFIG3_ENIDI;
+ } else {
+ reg1 &= ~(SMB_CONFIG1_ENAB | SMB_CONFIG1_FEN);
+ reg3 &= ~(SMB_CONFIG3_ENMI | SMB_CONFIG3_ENIDI);
+ }
+
+ writeb(reg1, bp + SMB_CORE_CONFIG_REG1);
+ writeb(reg3, bp + SMB_CORE_CONFIG_REG3);
+}
+
+static void pci1xxxx_i2c_set_freq(struct pci1xxxx_i2c *i2c)
+{
+ void __iomem *bp;
+
+ bp = i2c->i2c_base;
+ switch (i2c->freq) {
+ case I2C_MAX_STANDARD_MODE_FREQ:
+ writeb(SR_HOLD_TIME_100K_TICKS, bp + SMB_CORE_SR_HOLD_TIME_REG_OFF);
+ writel(SMB_IDLE_SCALING_100K, bp + SMB_CORE_IDLE_SCALING_REG_OFF);
+ writew(BUS_CLK_100K, bp + SMB_CORE_BUS_CLK_REG_OFF);
+ writel(CLK_SYNC_100K, bp + SMB_CORE_CLK_SYNC_REG_OFF);
+ writel(DATA_TIMING_100K, bp + SMB_CORE_DATA_TIMING_REG_OFF);
+ writel(TO_SCALING_100K, bp + SMB_CORE_TO_SCALING_REG_OFF);
+ break;
+
+ case I2C_MAX_FAST_MODE_PLUS_FREQ:
+ writeb(SR_HOLD_TIME_1000K_TICKS, bp + SMB_CORE_SR_HOLD_TIME_REG_OFF);
+ writel(SMB_IDLE_SCALING_1000K, bp + SMB_CORE_IDLE_SCALING_REG_OFF);
+ writew(BUS_CLK_1000K, bp + SMB_CORE_BUS_CLK_REG_OFF);
+ writel(CLK_SYNC_1000K, bp + SMB_CORE_CLK_SYNC_REG_OFF);
+ writel(DATA_TIMING_1000K, bp + SMB_CORE_DATA_TIMING_REG_OFF);
+ writel(TO_SCALING_1000K, bp + SMB_CORE_TO_SCALING_REG_OFF);
+ break;
+
+ case I2C_MAX_FAST_MODE_FREQ:
+ default:
+ writeb(SR_HOLD_TIME_400K_TICKS, bp + SMB_CORE_SR_HOLD_TIME_REG_OFF);
+ writel(SMB_IDLE_SCALING_400K, bp + SMB_CORE_IDLE_SCALING_REG_OFF);
+ writew(BUS_CLK_400K, bp + SMB_CORE_BUS_CLK_REG_OFF);
+ writel(CLK_SYNC_400K, bp + SMB_CORE_CLK_SYNC_REG_OFF);
+ writel(DATA_TIMING_400K, bp + SMB_CORE_DATA_TIMING_REG_OFF);
+ writel(TO_SCALING_400K, bp + SMB_CORE_TO_SCALING_REG_OFF);
+ break;
+ }
+}
+
+static void pci1xxxx_i2c_init(struct pci1xxxx_i2c *i2c)
+{
+ void __iomem *bp;
+ u8 regval;
+ u8 ret;
+
+ bp = i2c->i2c_base;
+ ret = set_sys_lock(i2c);
+ if (ret != -EPERM) {
+ regval = readl(bp + SMB_GPR_REG);
+ release_sys_lock(i2c);
+ } else {
+ /*
+ * Configure I2C Fast Mode as default frequency if unable
+ * to acquire sys lock.
+ */
+ regval = 0;
+ }
+
+ switch (regval) {
+ case 0:
+ i2c->freq = I2C_MAX_FAST_MODE_FREQ;
+ pci1xxxx_i2c_set_freq(i2c);
+ break;
+ case 1:
+ i2c->freq = I2C_MAX_STANDARD_MODE_FREQ;
+ pci1xxxx_i2c_set_freq(i2c);
+ break;
+ case 2:
+ i2c->freq = I2C_MAX_FAST_MODE_PLUS_FREQ;
+ pci1xxxx_i2c_set_freq(i2c);
+ break;
+ case 3:
+ default:
+ break;
+ }
+
+ pci1xxxx_i2c_config_padctrl(i2c, true);
+ i2c->flags |= I2C_FLAGS_DIRECT_MODE;
+ pci1xxxx_i2c_set_mode(i2c);
+
+ /*
+ * Added as a precaution since BUF_EMPTY in status register
+ * also trigered an Interrupt.
+ */
+ writeb(STA_BUF_EMPTY, bp + SMBUS_STATUS_REG_OFF);
+
+ /* Configure core I2c control registers. */
+ pci1xxxx_i2c_configure_core_reg(i2c, true);
+
+ /*
+ * Enable Pullup for the SMB alert pin which is just used for
+ * wakeup right now.
+ */
+ pci1xxxx_i2c_configure_smbalert_pin(i2c, true);
+}
+
+static void pci1xxxx_i2c_clear_flags(struct pci1xxxx_i2c *i2c)
+{
+ u8 regval;
+
+ /* Reset the internal buffer counters. */
+ pci1xxxx_i2c_reset_counters(i2c);
+
+ /* Clear low level interrupts. */
+ regval = COMPLETION_MNAKX | COMPLETION_IDLE | COMPLETION_MDONE;
+ writeb(regval, i2c->i2c_base + SMB_CORE_COMPLETION_REG_OFF3);
+ reinit_completion(&i2c->i2c_xfer_done);
+ pci1xxxx_ack_nw_layer_intr(i2c, ALL_NW_LAYER_INTERRUPTS);
+ pci1xxxx_ack_high_level_intr(i2c, ALL_HIGH_LAYER_INTR);
+}
+
+static int pci1xxxx_i2c_read(struct pci1xxxx_i2c *i2c, u8 slaveaddr,
+ unsigned char *buf, u16 total_len)
+{
+ unsigned long time_left;
+ u16 remainingbytes;
+ void __iomem *bp;
+ u8 transferlen;
+ int retval = 0;
+ u8 read_count;
+ u32 regval;
+ u16 count;
+
+ bp = i2c->i2c_base;
+
+ /* Enable I2C host controller by setting the ESO bit in the CONTROL REG. */
+ pci1xxxx_i2c_enable_ESO(i2c);
+ pci1xxxx_i2c_clear_flags(i2c);
+ pci1xxxx_config_nw_layer_intr(i2c, INTR_MSK_DMA_TERM, true);
+ pci1xxxx_i2c_config_high_level_intr(i2c, I2C_BUF_MSTR_INTR_MASK, true);
+
+ /*
+ * The I2C transfer could be more than 128 bytes. Our Core is
+ * capable of only sending 128 at a time.
+ * As far as the I2C read is concerned, initailly send the
+ * read slave address along with the number of bytes to read in
+ * ReadCount. After sending the slave address the interrupt
+ * is generated. On seeing the ACK for the slave address, reverse the
+ * buffer direction and run the DMA to initiate Read from slave.
+ */
+ for (count = 0; count < total_len; count += transferlen) {
+
+ /*
+ * Before start of any transaction clear the existing
+ * START/STOP conditions.
+ */
+ writeb(0x00, bp + SMB_CORE_CMD_REG_OFF1);
+ remainingbytes = total_len - count;
+ transferlen = min_t(u16, remainingbytes, (u16)SMBUS_BUF_MAX_SIZE);
+
+ /*
+ * Send STOP bit for the last chunk in the transaction.
+ * For I2C read transaction of more than BUF_SIZE, NACK should
+ * only be sent for the last read.
+ * Hence a bit FW_ACK is set for all the read chunks except for
+ * the last chunk. For the last chunk NACK should be sent and
+ * FW_ACK is cleared Send STOP only when I2C_FLAGS_STOP bit is
+ * set in the flags and only for the last transaction.
+ */
+ if ((count + transferlen >= total_len) &&
+ (i2c->flags & I2C_FLAGS_STOP)) {
+ pci1xxxx_i2c_set_clear_FW_ACK(i2c, false);
+ pci1xxxx_i2c_send_start_stop(i2c, 0);
+ } else {
+ pci1xxxx_i2c_set_clear_FW_ACK(i2c, true);
+ }
+
+ /* Send START bit for the first transaction. */
+ if (count == 0) {
+ pci1xxxx_i2c_set_transfer_dir(i2c, I2C_DIRN_WRITE);
+ pci1xxxx_i2c_send_start_stop(i2c, 1);
+
+ /* Write I2c buffer with just the slave addr. */
+ pci1xxxx_i2c_buffer_write(i2c, slaveaddr, 0, NULL);
+
+ /* Set the count. Readcount is the transfer bytes. */
+ pci1xxxx_i2c_set_count(i2c, 1, 1, transferlen);
+
+ /*
+ * Set the Auto_start_read bit so that the HW itself
+ * will take care of the read phase.
+ */
+ pci1xxxx_i2c_config_asr(i2c, true);
+ if (i2c->flags & I2C_FLAGS_SMB_BLK_READ)
+ pci1xxxx_i2c_set_readm(i2c, true);
+ } else {
+ pci1xxxx_i2c_set_count(i2c, 0, 0, transferlen);
+ pci1xxxx_i2c_config_asr(i2c, false);
+ pci1xxxx_i2c_clear_flags(i2c);
+ pci1xxxx_i2c_set_transfer_dir(i2c, I2C_DIRN_READ);
+ }
+
+ /* Start the DMA. */
+ pci1xxxx_i2c_start_DMA(i2c);
+
+ /* Wait for the DMA_TERM interrupt. */
+ time_left = wait_for_completion_timeout
+ (&i2c->i2c_xfer_done,
+ msecs_to_jiffies(PCI1XXXX_I2C_TIMEOUT_MS));
+ if (time_left == 0) {
+ /* Reset the I2C core to release the bus lock. */
+ pci1xxxx_i2c_init(i2c);
+ retval = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ /* Read the completion reg to know the reason for DMA_TERM. */
+ regval = readb(bp + SMB_CORE_COMPLETION_REG_OFF3);
+
+ /* Slave did not respond. */
+ if (regval & COMPLETION_MNAKX) {
+ writeb(COMPLETION_MNAKX, bp + SMB_CORE_COMPLETION_REG_OFF3);
+ retval = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (i2c->flags & I2C_FLAGS_SMB_BLK_READ) {
+ buf[0] = readb(bp + SMBUS_MST_BUF);
+ read_count = buf[0];
+ memcpy_fromio(&buf[1], bp + SMBUS_MST_BUF + 1, read_count);
+ } else {
+ memcpy_fromio(&buf[count], bp + SMBUS_MST_BUF, transferlen);
+ }
+ }
+
+cleanup:
+ /* Disable all the interrupts. */
+ pci1xxxx_config_nw_layer_intr(i2c, INTR_MSK_DMA_TERM, false);
+ pci1xxxx_i2c_config_high_level_intr(i2c, I2C_BUF_MSTR_INTR_MASK, false);
+ pci1xxxx_i2c_config_asr(i2c, false);
+ return retval;
+}
+
+static int pci1xxxx_i2c_write(struct pci1xxxx_i2c *i2c, u8 slaveaddr,
+ unsigned char *buf, u16 total_len)
+{
+ unsigned long time_left;
+ u16 remainingbytes;
+ u8 actualwritelen;
+ void __iomem *bp;
+ u8 transferlen;
+ int retval = 0;
+ u32 regval;
+ u16 count;
+
+ bp = i2c->i2c_base;
+
+ /* Enable I2C host controller by setting the ESO bit in the CONTROL REG. */
+ pci1xxxx_i2c_enable_ESO(i2c);
+
+ /* Set the Buffer direction. */
+ pci1xxxx_i2c_set_transfer_dir(i2c, I2C_DIRN_WRITE);
+ pci1xxxx_config_nw_layer_intr(i2c, INTR_MSK_DMA_TERM, true);
+ pci1xxxx_i2c_config_high_level_intr(i2c, I2C_BUF_MSTR_INTR_MASK, true);
+
+ /*
+ * The i2c transfer could be more than 128 bytes. Our Core is
+ * capable of only sending 128 at a time.
+ */
+ for (count = 0; count < total_len; count += transferlen) {
+ /*
+ * Before start of any transaction clear the existing
+ * START/STOP conditions.
+ */
+ writeb(0x00, bp + SMB_CORE_CMD_REG_OFF1);
+ pci1xxxx_i2c_clear_flags(i2c);
+ remainingbytes = total_len - count;
+
+ /* If it is the starting of the transaction send START. */
+ if (count == 0) {
+ pci1xxxx_i2c_send_start_stop(i2c, 1);
+
+ /* -1 for the slave address. */
+ transferlen = min_t(u16, (u16)SMBUS_BUF_MAX_SIZE - 1,
+ remainingbytes);
+ pci1xxxx_i2c_buffer_write(i2c, slaveaddr,
+ transferlen, &buf[count]);
+ /*
+ * The actual number of bytes written on the I2C bus
+ * is including the slave address.
+ */
+ actualwritelen = transferlen + 1;
+ } else {
+ transferlen = min_t(u16, (u16)SMBUS_BUF_MAX_SIZE,
+ remainingbytes);
+ pci1xxxx_i2c_buffer_write(i2c, 0x00, transferlen, &buf[count]);
+ actualwritelen = transferlen;
+ }
+
+ pci1xxxx_i2c_set_count(i2c, actualwritelen, actualwritelen, 0x00);
+
+ /*
+ * Send STOP only when I2C_FLAGS_STOP bit is set in the flags and
+ * only for the last transaction.
+ */
+ if (remainingbytes <= transferlen &&
+ (i2c->flags & I2C_FLAGS_STOP))
+ pci1xxxx_i2c_send_start_stop(i2c, 0);
+
+ pci1xxxx_i2c_start_DMA(i2c);
+
+ /*
+ * Wait for the DMA_TERM interrupt.
+ */
+ time_left = wait_for_completion_timeout(&i2c->i2c_xfer_done,
+ msecs_to_jiffies(PCI1XXXX_I2C_TIMEOUT_MS));
+ if (time_left == 0) {
+ /* Reset the I2C core to release the bus lock. */
+ pci1xxxx_i2c_init(i2c);
+ retval = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ regval = readb(bp + SMB_CORE_COMPLETION_REG_OFF3);
+ if (regval & COMPLETION_MNAKX) {
+ writeb(COMPLETION_MNAKX, i2c->i2c_base +
+ SMB_CORE_COMPLETION_REG_OFF3);
+ retval = -ETIMEDOUT;
+ goto cleanup;
+ }
+ }
+cleanup:
+ /* Disable all the interrupts. */
+ pci1xxxx_config_nw_layer_intr(i2c, INTR_MSK_DMA_TERM, false);
+ pci1xxxx_i2c_config_high_level_intr(i2c, I2C_BUF_MSTR_INTR_MASK, false);
+
+ return retval;
+}
+
+static int pci1xxxx_i2c_xfer(struct i2c_adapter *adap,
+ struct i2c_msg *msgs, int num)
+{
+ struct pci1xxxx_i2c *i2c = i2c_get_adapdata(adap);
+ u8 slaveaddr;
+ int retval;
+ u32 i;
+
+ i2c->i2c_xfer_in_progress = true;
+ for (i = 0; i < num; i++) {
+ slaveaddr = i2c_8bit_addr_from_msg(&msgs[i]);
+
+ /*
+ * Send the STOP bit if the transfer is the final one or
+ * if the I2C_M_STOP flag is set.
+ */
+ if ((i == num - 1) || (msgs[i].flags & I2C_M_STOP))
+ i2c->flags |= I2C_FLAGS_STOP;
+ else
+ i2c->flags &= ~I2C_FLAGS_STOP;
+
+ if (msgs[i].flags & I2C_M_RECV_LEN)
+ i2c->flags |= I2C_FLAGS_SMB_BLK_READ;
+ else
+ i2c->flags &= ~I2C_FLAGS_SMB_BLK_READ;
+
+ if (msgs[i].flags & I2C_M_RD)
+ retval = pci1xxxx_i2c_read(i2c, slaveaddr,
+ msgs[i].buf, msgs[i].len);
+ else
+ retval = pci1xxxx_i2c_write(i2c, slaveaddr,
+ msgs[i].buf, msgs[i].len);
+
+ if (retval < 0)
+ break;
+ }
+ i2c->i2c_xfer_in_progress = false;
+
+ if (retval < 0)
+ return retval;
+
+ return num;
+}
+
+/*
+ * List of supported functions by the driver.
+ */
+static u32 pci1xxxx_i2c_get_funcs(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_PROTOCOL_MANGLING |
+ I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
+ I2C_FUNC_SMBUS_READ_BYTE | I2C_FUNC_SMBUS_WRITE_BYTE |
+ I2C_FUNC_SMBUS_READ_BYTE_DATA |
+ I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
+ I2C_FUNC_SMBUS_READ_WORD_DATA |
+ I2C_FUNC_SMBUS_WRITE_WORD_DATA |
+ I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_READ_BLOCK_DATA |
+ I2C_FUNC_SMBUS_WRITE_BLOCK_DATA;
+}
+
+static const struct i2c_algorithm pci1xxxx_i2c_algo = {
+ .master_xfer = pci1xxxx_i2c_xfer,
+ .functionality = pci1xxxx_i2c_get_funcs,
+};
+
+static const struct i2c_adapter pci1xxxx_i2c_ops = {
+ .owner = THIS_MODULE,
+ .name = "Pci1xxxx I2C Adapter",
+ .algo = &pci1xxxx_i2c_algo,
+};
+
+static int pci1xxxx_i2c_suspend(struct device *dev)
+{
+ struct pci1xxxx_i2c *i2c = dev_get_drvdata(dev);
+ struct pci_dev *pdev = to_pci_dev(dev);
+ void __iomem *bp;
+ u32 regval;
+
+ bp = i2c->i2c_base;
+ i2c_mark_adapter_suspended(&i2c->adap);
+
+ /*
+ * If the system is put into 'suspend' state when the I2C transfer is in
+ * progress, wait until the transfer completes.
+ */
+ while (i2c->i2c_xfer_in_progress)
+ msleep(20);
+
+ pci1xxxx_i2c_config_high_level_intr(i2c, SMBALERT_WAKE_INTR_MASK, true);
+
+ /*
+ * Enable the PERST_DIS bit to mask the PERST from resetting the core
+ * registers.
+ */
+ regval = readl(bp + SMBUS_RESET_REG);
+ regval |= PERI_SMBUS_D3_RESET_DIS;
+ writel(regval, bp + SMBUS_RESET_REG);
+
+ /* Enable PCI wake in the PMCSR register. */
+ device_set_wakeup_enable(dev, TRUE);
+ pci_wake_from_d3(pdev, TRUE);
+
+ return 0;
+}
+
+static int pci1xxxx_i2c_resume(struct device *dev)
+{
+ struct pci1xxxx_i2c *i2c = dev_get_drvdata(dev);
+ struct pci_dev *pdev = to_pci_dev(dev);
+ void __iomem *bp;
+ u32 regval;
+
+ bp = i2c->i2c_base;
+ regval = readw(bp + SMBUS_GEN_INT_STAT_REG_OFF);
+ writew(regval, bp + SMBUS_GEN_INT_STAT_REG_OFF);
+ pci1xxxx_i2c_config_high_level_intr(i2c, SMBALERT_WAKE_INTR_MASK, false);
+ regval = readl(bp + SMBUS_RESET_REG);
+ regval &= ~PERI_SMBUS_D3_RESET_DIS;
+ writel(regval, bp + SMBUS_RESET_REG);
+ i2c_mark_adapter_resumed(&i2c->adap);
+ pci_wake_from_d3(pdev, false);
+ return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(pci1xxxx_i2c_pm_ops, pci1xxxx_i2c_suspend,
+ pci1xxxx_i2c_resume);
+
+static void pci1xxxx_i2c_shutdown(struct pci1xxxx_i2c *i2c)
+{
+ pci1xxxx_i2c_config_padctrl(i2c, false);
+ pci1xxxx_i2c_configure_core_reg(i2c, false);
+}
+
+static int pci1xxxx_i2c_probe_pci(struct pci_dev *pdev,
+ const struct pci_device_id *ent)
+{
+ struct pci1xxxx_i2c *i2c;
+ struct device *dev;
+ int ret;
+
+ dev = &pdev->dev;
+ i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL);
+ if (!i2c)
+ return -ENOMEM;
+
+ pci_set_drvdata(pdev, i2c);
+ i2c->i2c_xfer_in_progress = false;
+
+ ret = pcim_enable_device(pdev);
+ if (ret)
+ return ret;
+
+ pci_set_master(pdev);
+
+ /*
+ * We are getting the base address of the SMB core. SMB core uses
+ * BAR0 and size is 32K.
+ */
+ ret = pcim_iomap_regions(pdev, BIT(0), pci_name(pdev));
+ if (ret < 0)
+ return -ENOMEM;
+
+ i2c->i2c_base = pcim_iomap_table(pdev)[0];
+ init_completion(&i2c->i2c_xfer_done);
+ pci1xxxx_i2c_init(i2c);
+
+ ret = devm_add_action(dev, (void (*)(void *))pci1xxxx_i2c_shutdown, i2c);
+ if (ret)
+ return ret;
+
+ ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
+ if (ret < 0)
+ return ret;
+
+ /* Register the isr. We are not using any isr flags here. */
+ ret = devm_request_irq(dev, pci_irq_vector(pdev, 0), pci1xxxx_i2c_isr,
+ PCI1XXXX_IRQ_FLAGS, pci_name(pdev), i2c);
+ if (ret)
+ return ret;
+
+ i2c->adap = pci1xxxx_i2c_ops;
+ i2c->adap.class = I2C_CLASS_SPD;
+ i2c->adap.dev.parent = dev;
+
+ snprintf(i2c->adap.name, sizeof(i2c->adap.name),
+ "MCHP PCI1xxxx i2c adapter at %s", pci_name(pdev));
+
+ i2c_set_adapdata(&i2c->adap, i2c);
+
+ ret = devm_i2c_add_adapter(dev, &i2c->adap);
+ if (ret)
+ return dev_err_probe(dev, ret, "i2c add adapter failed\n");
+
+ return 0;
+}
+
+static const struct pci_device_id pci1xxxx_i2c_pci_id_table[] = {
+ { PCI_VDEVICE(EFAR, 0xA003) },
+ { PCI_VDEVICE(EFAR, 0xA013) },
+ { PCI_VDEVICE(EFAR, 0xA023) },
+ { PCI_VDEVICE(EFAR, 0xA033) },
+ { PCI_VDEVICE(EFAR, 0xA043) },
+ { }
+};
+MODULE_DEVICE_TABLE(pci, pci1xxxx_i2c_pci_id_table);
+
+static struct pci_driver pci1xxxx_i2c_pci_driver = {
+ .name = "i2c-mchp-pci1xxxx",
+ .id_table = pci1xxxx_i2c_pci_id_table,
+ .probe = pci1xxxx_i2c_probe_pci,
+ .driver = {
+ .pm = pm_sleep_ptr(&pci1xxxx_i2c_pm_ops),
+ },
+};
+module_pci_driver(pci1xxxx_i2c_pci_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Tharun Kumar P<tharunkumar.pasumarthi@xxxxxxxxxxxxx>");
+MODULE_AUTHOR("Kumaravel Thiagarajan <kumaravel.thiagarajan@xxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Microchip Technology Inc. pci1xxxx I2C bus driver");
--
2.25.1