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Subject[PATCH v5 2/2] i2c: New bus driver for the Qualcomm QUP I2C controller
Date
This bus driver supports the QUP i2c hardware controller in the Qualcomm SOCs.
The Qualcomm Universal Peripheral Engine (QUP) is a general purpose data path
engine with input/output FIFOs and an embedded i2c mini-core. The driver
supports FIFO mode (for low bandwidth applications) and block mode (interrupt
generated for each block-size data transfer).

Cc: Andy Gross <agross@codeaurora.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
---
drivers/i2c/busses/Kconfig | 10 +
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-qup.c | 768 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 779 insertions(+)
create mode 100644 drivers/i2c/busses/i2c-qup.c

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index f5ed031..f994461 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -648,6 +648,16 @@ config I2C_PXA_SLAVE
is necessary for systems where the PXA may be a target on the
I2C bus.

+config I2C_QUP
+ tristate "Qualcomm QUP based I2C controller"
+ depends on ARCH_QCOM
+ help
+ If you say yes to this option, support will be included for the
+ built-in I2C interface on the Qualcomm SoCs.
+
+ This driver can also be built as a module. If so, the module
+ will be called i2c-qup.
+
config I2C_RIIC
tristate "Renesas RIIC adapter"
depends on ARCH_SHMOBILE || COMPILE_TEST
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index a08931f..bf2257b 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -63,6 +63,7 @@ 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-$(CONFIG_I2C_QUP) += i2c-qup.o
obj-$(CONFIG_I2C_RIIC) += i2c-riic.o
obj-$(CONFIG_I2C_S3C2410) += i2c-s3c2410.o
obj-$(CONFIG_I2C_S6000) += i2c-s6000.o
diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c
new file mode 100644
index 0000000..0c844bf
--- /dev/null
+++ b/drivers/i2c/busses/i2c-qup.c
@@ -0,0 +1,768 @@
+/*
+ * Copyright (c) 2009-2013, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2014, Sony Mobile Communications AB.
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.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/platform_device.h>
+#include <linux/pm_runtime.h>
+
+/* QUP Registers */
+#define QUP_CONFIG 0x000
+#define QUP_STATE 0x004
+#define QUP_IO_MODE 0x008
+#define QUP_SW_RESET 0x00c
+#define QUP_OPERATIONAL 0x018
+#define QUP_ERROR_FLAGS 0x01c
+#define QUP_ERROR_FLAGS_EN 0x020
+#define QUP_HW_VERSION 0x030
+#define QUP_MX_OUTPUT_CNT 0x100
+#define QUP_OUT_FIFO_BASE 0x110
+#define QUP_MX_WRITE_CNT 0x150
+#define QUP_MX_INPUT_CNT 0x200
+#define QUP_MX_READ_CNT 0x208
+#define QUP_IN_FIFO_BASE 0x218
+#define QUP_I2C_CLK_CTL 0x400
+#define QUP_I2C_STATUS 0x404
+
+/* QUP States and reset values */
+#define QUP_RESET_STATE 0
+#define QUP_RUN_STATE 1
+#define QUP_PAUSE_STATE 3
+#define QUP_STATE_MASK 3
+
+#define QUP_STATE_VALID BIT(2)
+#define QUP_I2C_MAST_GEN BIT(4)
+
+#define QUP_OPERATIONAL_RESET 0x000ff0
+#define QUP_I2C_STATUS_RESET 0xfffffc
+
+/* QUP OPERATIONAL FLAGS */
+#define QUP_I2C_NACK_FLAG BIT(3)
+#define QUP_OUT_NOT_EMPTY BIT(4)
+#define QUP_IN_NOT_EMPTY BIT(5)
+#define QUP_OUT_FULL BIT(6)
+#define QUP_OUT_SVC_FLAG BIT(8)
+#define QUP_IN_SVC_FLAG BIT(9)
+#define QUP_MX_OUTPUT_DONE BIT(10)
+#define QUP_MX_INPUT_DONE BIT(11)
+
+/* I2C mini core related values */
+#define QUP_CLOCK_AUTO_GATE BIT(13)
+#define I2C_MINI_CORE (2 << 8)
+#define I2C_N_VAL 15
+/* Most significant word offset in FIFO port */
+#define QUP_MSW_SHIFT (I2C_N_VAL + 1)
+
+/* Packing/Unpacking words in FIFOs, and IO modes */
+#define QUP_OUTPUT_BLK_MODE (1 << 10)
+#define QUP_INPUT_BLK_MODE (1 << 12)
+#define QUP_UNPACK_EN BIT(14)
+#define QUP_PACK_EN BIT(15)
+
+#define QUP_REPACK_EN (QUP_UNPACK_EN | QUP_PACK_EN)
+
+#define QUP_OUTPUT_BLOCK_SIZE(x)(((x) >> 0) & 0x03)
+#define QUP_OUTPUT_FIFO_SIZE(x) (((x) >> 2) & 0x07)
+#define QUP_INPUT_BLOCK_SIZE(x) (((x) >> 5) & 0x03)
+#define QUP_INPUT_FIFO_SIZE(x) (((x) >> 7) & 0x07)
+
+/* QUP tags */
+#define QUP_TAG_START (1 << 8)
+#define QUP_TAG_DATA (2 << 8)
+#define QUP_TAG_STOP (3 << 8)
+#define QUP_TAG_REC (4 << 8)
+
+/* Status, Error flags */
+#define I2C_STATUS_WR_BUFFER_FULL BIT(0)
+#define I2C_STATUS_BUS_ACTIVE BIT(8)
+#define I2C_STATUS_ERROR_MASK 0x38000fc
+#define QUP_STATUS_ERROR_FLAGS 0x7c
+
+#define QUP_READ_LIMIT 256
+
+struct qup_i2c_dev {
+ struct device *dev;
+ void __iomem *base;
+ int irq;
+ struct clk *clk;
+ struct clk *pclk;
+ struct i2c_adapter adap;
+
+ int clk_ctl;
+ int out_fifo_sz;
+ int in_fifo_sz;
+ int out_blk_sz;
+ int in_blk_sz;
+
+ unsigned long one_byte_t;
+
+ struct i2c_msg *msg;
+ /* Current posion in user message buffer */
+ int pos;
+ /* I2C protocol errors */
+ u32 bus_err;
+ /* QUP core errors */
+ u32 qup_err;
+
+ struct completion xfer;
+};
+
+static irqreturn_t qup_i2c_interrupt(int irq, void *dev)
+{
+ struct qup_i2c_dev *qup = dev;
+ u32 bus_err;
+ u32 qup_err;
+ u32 opflags;
+
+ bus_err = readl(qup->base + QUP_I2C_STATUS);
+ qup_err = readl(qup->base + QUP_ERROR_FLAGS);
+ opflags = readl(qup->base + QUP_OPERATIONAL);
+
+ if (!qup->msg) {
+ /* Clear Error interrupt */
+ writel(QUP_RESET_STATE, qup->base + QUP_STATE);
+ return IRQ_HANDLED;
+ }
+
+ bus_err &= I2C_STATUS_ERROR_MASK;
+ qup_err &= QUP_STATUS_ERROR_FLAGS;
+
+ if (qup_err) {
+ /* Clear Error interrupt */
+ writel(qup_err, qup->base + QUP_ERROR_FLAGS);
+ goto done;
+ }
+
+ if (bus_err) {
+ /* Clear Error interrupt */
+ writel(QUP_RESET_STATE, qup->base + QUP_STATE);
+ goto done;
+ }
+
+ if (opflags & QUP_IN_SVC_FLAG)
+ writel(QUP_IN_SVC_FLAG, qup->base + QUP_OPERATIONAL);
+
+ if (opflags & QUP_OUT_SVC_FLAG)
+ writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL);
+
+done:
+ qup->qup_err = qup_err;
+ qup->bus_err = bus_err;
+ complete(&qup->xfer);
+ return IRQ_HANDLED;
+}
+
+static int qup_i2c_poll_state_mask(struct qup_i2c_dev *qup,
+ u32 req_state, u32 req_mask)
+{
+ int retries = 1;
+ u32 state;
+
+ /*
+ * State transition takes 3 AHB clocks cycles + 3 I2C master clock
+ * cycles. So retry once after a 1uS delay.
+ */
+ do {
+ state = readl(qup->base + QUP_STATE);
+
+ if (state & QUP_STATE_VALID &&
+ (state & req_mask) == req_state)
+ return 0;
+
+ udelay(1);
+ } while (retries--);
+
+ return -ETIMEDOUT;
+}
+
+static int qup_i2c_poll_state(struct qup_i2c_dev *qup, u32 req_state)
+{
+ return qup_i2c_poll_state_mask(qup, req_state, QUP_STATE_MASK);
+}
+
+static int qup_i2c_poll_state_valid(struct qup_i2c_dev *qup)
+{
+ return qup_i2c_poll_state_mask(qup, 0, 0);
+}
+
+static int qup_i2c_poll_state_i2c_master(struct qup_i2c_dev *qup)
+{
+ return qup_i2c_poll_state_mask(qup, QUP_I2C_MAST_GEN, QUP_I2C_MAST_GEN);
+}
+
+static int qup_i2c_change_state(struct qup_i2c_dev *qup, u32 state)
+{
+ if (qup_i2c_poll_state_valid(qup) != 0)
+ return -EIO;
+
+ writel(state, qup->base + QUP_STATE);
+
+ if (qup_i2c_poll_state(qup, state) != 0)
+ return -EIO;
+ return 0;
+}
+
+static int qup_i2c_wait_writeready(struct qup_i2c_dev *qup)
+{
+ unsigned long timeout;
+ u32 opflags;
+ u32 status;
+
+ timeout = jiffies + HZ;
+
+ for (;;) {
+ opflags = readl(qup->base + QUP_OPERATIONAL);
+ status = readl(qup->base + QUP_I2C_STATUS);
+
+ if (!(opflags & QUP_OUT_NOT_EMPTY) &&
+ !(status & I2C_STATUS_BUS_ACTIVE))
+ return 0;
+
+ if (time_after(jiffies, timeout))
+ return -ETIMEDOUT;
+
+ usleep_range(qup->one_byte_t, qup->one_byte_t * 2);
+ }
+}
+
+static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+{
+ /* Number of entries to shift out, including the start */
+ int total = msg->len + 1;
+
+ if (total < qup->out_fifo_sz) {
+ /* FIFO mode */
+ writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE);
+ writel(total, qup->base + QUP_MX_WRITE_CNT);
+ } else {
+ /* BLOCK mode (transfer data on chunks) */
+ writel(QUP_OUTPUT_BLK_MODE | QUP_REPACK_EN,
+ qup->base + QUP_IO_MODE);
+ writel(total, qup->base + QUP_MX_OUTPUT_CNT);
+ }
+}
+
+static void qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+{
+ u32 addr = msg->addr << 1;
+ u32 qup_tag;
+ u32 opflags;
+ int idx;
+ u32 val;
+
+ if (qup->pos == 0) {
+ val = QUP_TAG_START | addr;
+ idx = 1;
+ } else {
+ val = 0;
+ idx = 0;
+ }
+
+ while (qup->pos < msg->len) {
+ /* Check that there's space in the FIFO for our pair */
+ opflags = readl(qup->base + QUP_OPERATIONAL);
+ if (opflags & QUP_OUT_FULL)
+ break;
+
+ if (qup->pos == msg->len - 1)
+ qup_tag = QUP_TAG_STOP;
+ else
+ qup_tag = QUP_TAG_DATA;
+
+ if (idx & 1)
+ val |= (qup_tag | msg->buf[qup->pos]) << QUP_MSW_SHIFT;
+ else
+ val = qup_tag | msg->buf[qup->pos];
+
+ /* Write out the pair and the last odd value */
+ if (idx & 1 || qup->pos == msg->len - 1)
+ writel(val, qup->base + QUP_OUT_FIFO_BASE);
+
+ qup->pos++;
+ idx++;
+ }
+}
+
+static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+{
+ unsigned long left;
+ int ret;
+
+ qup->msg = msg;
+ qup->pos = 0;
+
+ enable_irq(qup->irq);
+
+ qup_i2c_set_write_mode(qup, msg);
+
+ ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+ if (ret)
+ goto err;
+
+ writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
+
+ do {
+ ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
+ if (ret)
+ goto err;
+
+ qup_i2c_issue_write(qup, msg);
+
+ ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+ if (ret)
+ goto err;
+
+ left = wait_for_completion_timeout(&qup->xfer, HZ);
+ if (!left) {
+ writel(1, qup->base + QUP_SW_RESET);
+ ret = -ETIMEDOUT;
+ goto err;
+ }
+
+ if (qup->bus_err || qup->qup_err) {
+ if (qup->bus_err & QUP_I2C_NACK_FLAG)
+ dev_err(qup->dev, "NACK from %x\n", msg->addr);
+ ret = -EIO;
+ goto err;
+ }
+ } while (qup->pos < msg->len);
+
+ /* Wait for the outstanding data in the fifo to drain */
+ ret = qup_i2c_wait_writeready(qup);
+
+err:
+ disable_irq(qup->irq);
+ qup->msg = NULL;
+
+ return ret;
+}
+
+static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len)
+{
+ if (len < qup->in_fifo_sz) {
+ /* FIFO mode */
+ writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE);
+ writel(len, qup->base + QUP_MX_READ_CNT);
+ } else {
+ /* BLOCK mode (transfer data on chunks) */
+ writel(QUP_INPUT_BLK_MODE | QUP_REPACK_EN,
+ qup->base + QUP_IO_MODE);
+ writel(len, qup->base + QUP_MX_INPUT_CNT);
+ }
+}
+
+static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+{
+ u32 addr, len, val;
+
+ addr = (msg->addr << 1) | 1;
+
+ /* 0 is used to specify a length 256 (QUP_READ_LIMIT) */
+ len = (msg->len == QUP_READ_LIMIT) ? 0 : msg->len;
+
+ val = ((QUP_TAG_REC | len) << QUP_MSW_SHIFT) | QUP_TAG_START | addr;
+ writel(val, qup->base + QUP_OUT_FIFO_BASE);
+}
+
+
+static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+{
+ u32 opflags;
+ u32 val = 0;
+ int idx;
+
+ for (idx = 0; qup->pos < msg->len; idx++) {
+ if ((idx & 1) == 0) {
+ /* Check that FIFO have data */
+ opflags = readl(qup->base + QUP_OPERATIONAL);
+ if (!(opflags & QUP_IN_NOT_EMPTY))
+ break;
+
+ /* Reading 2 words at time */
+ val = readl(qup->base + QUP_IN_FIFO_BASE);
+
+ msg->buf[qup->pos++] = val & 0xFF;
+ } else {
+ msg->buf[qup->pos++] = val >> QUP_MSW_SHIFT;
+ }
+ }
+}
+
+static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg)
+{
+ unsigned long left;
+ int ret;
+
+ /*
+ * The QUP block will issue a NACK and STOP on the bus when reaching
+ * the end of the read, the length of the read is specified as one byte
+ * which limits the possible read to 256 (QUP_READ_LIMIT) bytes.
+ */
+ if (msg->len > QUP_READ_LIMIT) {
+ dev_err(qup->dev, "HW not capable of reads over %d bytes\n",
+ QUP_READ_LIMIT);
+ return -EINVAL;
+ }
+
+ qup->msg = msg;
+ qup->pos = 0;
+
+ enable_irq(qup->irq);
+
+ qup_i2c_set_read_mode(qup, msg->len);
+
+ ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+ if (ret)
+ goto err;
+
+ writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
+
+ ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
+ if (ret)
+ goto err;
+
+ qup_i2c_issue_read(qup, msg);
+
+ ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+ if (ret)
+ goto err;
+
+ do {
+ left = wait_for_completion_timeout(&qup->xfer, HZ);
+ if (!left) {
+ writel(1, qup->base + QUP_SW_RESET);
+ ret = -ETIMEDOUT;
+ goto err;
+ }
+
+ if (qup->bus_err || qup->qup_err) {
+ if (qup->bus_err & QUP_I2C_NACK_FLAG)
+ dev_err(qup->dev, "NACK from %x\n", msg->addr);
+ ret = -EIO;
+ goto err;
+ }
+
+ qup_i2c_read_fifo(qup, msg);
+ } while (qup->pos < msg->len);
+
+err:
+ disable_irq(qup->irq);
+ qup->msg = NULL;
+
+ return ret;
+}
+
+static int qup_i2c_xfer(struct i2c_adapter *adap,
+ struct i2c_msg msgs[],
+ int num)
+{
+ struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
+ int ret, idx;
+
+ ret = pm_runtime_get_sync(qup->dev);
+ if (IS_ERR_VALUE(ret))
+ goto out;
+
+ writel(1, qup->base + QUP_SW_RESET);
+ ret = qup_i2c_poll_state(qup, QUP_RESET_STATE);
+ if (ret)
+ goto out;
+
+ /* Configure QUP as I2C mini core */
+ writel(I2C_MINI_CORE | I2C_N_VAL, qup->base + QUP_CONFIG);
+
+ for (idx = 0; idx < num; idx++) {
+ if (msgs[idx].len == 0) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (qup_i2c_poll_state_i2c_master(qup)) {
+ ret = -EIO;
+ goto out;
+ }
+
+ if (msgs[idx].flags & I2C_M_RD)
+ ret = qup_i2c_read_one(qup, &msgs[idx]);
+ else
+ ret = qup_i2c_write_one(qup, &msgs[idx]);
+
+ if (ret)
+ break;
+
+ ret = qup_i2c_change_state(qup, QUP_RESET_STATE);
+ if (ret)
+ break;
+ }
+
+ if (ret == 0)
+ ret = num;
+out:
+
+ pm_runtime_mark_last_busy(qup->dev);
+ pm_runtime_put_autosuspend(qup->dev);
+
+ return ret;
+}
+
+static u32 qup_i2c_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+}
+
+static const struct i2c_algorithm qup_i2c_algo = {
+ .master_xfer = qup_i2c_xfer,
+ .functionality = qup_i2c_func,
+};
+
+static void qup_i2c_enable_clocks(struct qup_i2c_dev *qup)
+{
+ clk_prepare_enable(qup->clk);
+ clk_prepare_enable(qup->pclk);
+}
+
+static void qup_i2c_disable_clocks(struct qup_i2c_dev *qup)
+{
+ u32 config;
+
+ qup_i2c_change_state(qup, QUP_RESET_STATE);
+ clk_disable_unprepare(qup->clk);
+ config = readl(qup->base + QUP_CONFIG);
+ config |= QUP_CLOCK_AUTO_GATE;
+ writel(config, qup->base + QUP_CONFIG);
+ clk_disable_unprepare(qup->pclk);
+}
+
+static int qup_i2c_probe(struct platform_device *pdev)
+{
+ static const int blk_sizes[] = {4, 16, 32};
+ struct device_node *node = pdev->dev.of_node;
+ struct qup_i2c_dev *qup;
+ unsigned long one_bit_t;
+ struct resource *res;
+ u32 io_mode, hw_ver, size;
+ int ret, fs_div, hs_div;
+ int src_clk_freq;
+ int clk_freq = 100000;
+
+ qup = devm_kzalloc(&pdev->dev, sizeof(*qup), GFP_KERNEL);
+ if (!qup)
+ return -ENOMEM;
+
+ qup->dev = &pdev->dev;
+ init_completion(&qup->xfer);
+ platform_set_drvdata(pdev, qup);
+
+ of_property_read_u32(node, "clock-frequency", &clk_freq);
+
+ /* We support frequencies up to FAST Mode (400KHz) */
+ if (!clk_freq || clk_freq > 400000) {
+ dev_err(qup->dev, "clock frequency not supported %d\n",
+ clk_freq);
+ return -EINVAL;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ qup->base = devm_ioremap_resource(qup->dev, res);
+ if (IS_ERR(qup->base))
+ return PTR_ERR(qup->base);
+
+ qup->irq = platform_get_irq(pdev, 0);
+ if (qup->irq < 0) {
+ dev_err(qup->dev, "No IRQ defined\n");
+ return qup->irq;
+ }
+
+ qup->clk = devm_clk_get(qup->dev, "core");
+ if (IS_ERR(qup->clk)) {
+ dev_err(qup->dev, "Could not get core clock\n");
+ return PTR_ERR(qup->clk);
+ }
+
+ qup->pclk = devm_clk_get(qup->dev, "iface");
+ if (IS_ERR(qup->pclk)) {
+ dev_err(qup->dev, "Could not get iface clock\n");
+ return PTR_ERR(qup->pclk);
+ }
+
+ qup_i2c_enable_clocks(qup);
+
+ /*
+ * Bootloaders might leave a pending interrupt on certain QUP's,
+ * so we reset the core before registering for interrupts.
+ */
+ writel(1, qup->base + QUP_SW_RESET);
+ ret = qup_i2c_poll_state_valid(qup);
+ if (ret)
+ goto fail;
+
+ ret = devm_request_irq(qup->dev, qup->irq, qup_i2c_interrupt,
+ IRQF_TRIGGER_HIGH, "i2c_qup", qup);
+ if (ret) {
+ dev_err(qup->dev, "Request %d IRQ failed\n", qup->irq);
+ goto fail;
+ }
+ disable_irq(qup->irq);
+
+ hw_ver = readl(qup->base + QUP_HW_VERSION);
+ dev_dbg(qup->dev, "Revision %x\n", hw_ver);
+
+ io_mode = readl(qup->base + QUP_IO_MODE);
+
+ /*
+ * The block/fifo size w.r.t. 'actual data' is 1/2 due to 'tag'
+ * associated with each byte written/received
+ */
+ size = QUP_OUTPUT_BLOCK_SIZE(io_mode);
+ if (size > ARRAY_SIZE(blk_sizes))
+ return -EIO;
+ qup->out_blk_sz = blk_sizes[size] / 2;
+
+ size = QUP_INPUT_BLOCK_SIZE(io_mode);
+ if (size > ARRAY_SIZE(blk_sizes))
+ return -EIO;
+ qup->in_blk_sz = blk_sizes[size] / 2;
+
+ size = QUP_OUTPUT_FIFO_SIZE(io_mode);
+ qup->out_fifo_sz = qup->out_blk_sz * (2 << size);
+
+ size = QUP_INPUT_FIFO_SIZE(io_mode);
+ qup->in_fifo_sz = qup->in_blk_sz * (2 << size);
+
+ src_clk_freq = clk_get_rate(qup->clk);
+ fs_div = ((src_clk_freq / clk_freq) / 2) - 3;
+ hs_div = 3;
+ qup->clk_ctl = (hs_div << 8) | (fs_div & 0xff);
+
+ /*
+ * Time it takes for a byte to be clocked out on the bus.
+ * Each byte takes 9 clock cycles (8 bits + 1 ack).
+ */
+ one_bit_t = (USEC_PER_SEC / clk_freq) + 1;
+ qup->one_byte_t = one_bit_t * 9;
+
+ dev_dbg(qup->dev, "IN:block:%d, fifo:%d, OUT:block:%d, fifo:%d\n",
+ qup->in_blk_sz, qup->in_fifo_sz,
+ qup->out_blk_sz, qup->out_fifo_sz);
+
+ i2c_set_adapdata(&qup->adap, qup);
+ qup->adap.algo = &qup_i2c_algo;
+ qup->adap.dev.parent = qup->dev;
+ qup->adap.dev.of_node = pdev->dev.of_node;
+ strlcpy(qup->adap.name, "QUP I2C adapter", sizeof(qup->adap.name));
+
+ ret = i2c_add_adapter(&qup->adap);
+ if (ret)
+ goto fail;
+
+ pm_runtime_set_autosuspend_delay(qup->dev, MSEC_PER_SEC);
+ pm_runtime_use_autosuspend(qup->dev);
+ pm_runtime_set_active(qup->dev);
+ pm_runtime_enable(qup->dev);
+ return 0;
+
+fail:
+ qup_i2c_disable_clocks(qup);
+ return ret;
+}
+
+static int qup_i2c_remove(struct platform_device *pdev)
+{
+ struct qup_i2c_dev *qup = platform_get_drvdata(pdev);
+
+ disable_irq(qup->irq);
+ qup_i2c_disable_clocks(qup);
+ i2c_del_adapter(&qup->adap);
+ pm_runtime_disable(qup->dev);
+ pm_runtime_set_suspended(qup->dev);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int qup_i2c_pm_suspend_runtime(struct device *device)
+{
+ struct qup_i2c_dev *qup = dev_get_drvdata(device);
+
+ dev_dbg(device, "pm_runtime: suspending...\n");
+ qup_i2c_disable_clocks(qup);
+ return 0;
+}
+
+static int qup_i2c_pm_resume_runtime(struct device *device)
+{
+ struct qup_i2c_dev *qup = dev_get_drvdata(device);
+
+ dev_dbg(device, "pm_runtime: resuming...\n");
+ qup_i2c_enable_clocks(qup);
+ return 0;
+}
+#endif
+
+#ifdef CONFIG_PM_SLEEP
+static int qup_i2c_suspend(struct device *device)
+{
+ qup_i2c_pm_suspend_runtime(device);
+ return 0;
+}
+
+static int qup_i2c_resume(struct device *device)
+{
+ qup_i2c_pm_resume_runtime(device);
+ pm_runtime_mark_last_busy(device);
+ pm_request_autosuspend(device);
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops qup_i2c_qup_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(
+ qup_i2c_suspend,
+ qup_i2c_resume)
+ SET_RUNTIME_PM_OPS(
+ qup_i2c_pm_suspend_runtime,
+ qup_i2c_pm_resume_runtime,
+ NULL)
+};
+
+static const struct of_device_id qup_i2c_dt_match[] = {
+ { .compatible = "qcom,i2c-qup-v1.1.1" },
+ { .compatible = "qcom,i2c-qup-v2.1.1" },
+ { .compatible = "qcom,i2c-qup-v2.2.1" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, qup_i2c_dt_match);
+
+static struct platform_driver qup_i2c_driver = {
+ .probe = qup_i2c_probe,
+ .remove = qup_i2c_remove,
+ .driver = {
+ .name = "i2c_qup",
+ .owner = THIS_MODULE,
+ .pm = &qup_i2c_qup_pm_ops,
+ .of_match_table = qup_i2c_dt_match,
+ },
+};
+
+module_platform_driver(qup_i2c_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:i2c_qup");
--
1.7.9.5


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