Adds support for High Speed I2C driver found in Exynos5 and later
SoCs from Samsung. This driver currently supports Auto mode.

Driver only supports Device Tree method.

Signed-off-by: Taekgyun Ko <taeggyun...@samsung.com>
Signed-off-by: Naveen Krishna Chatradhi <ch.nav...@samsung.com>
---
 drivers/i2c/busses/Kconfig       |    6 +
 drivers/i2c/busses/Makefile      |    1 +
 drivers/i2c/busses/i2c-exynos5.c |  758 ++++++++++++++++++++++++++++++++++++++
 drivers/i2c/busses/i2c-exynos5.h |   80 ++++
 4 files changed, 845 insertions(+)
 create mode 100644 drivers/i2c/busses/i2c-exynos5.c
 create mode 100644 drivers/i2c/busses/i2c-exynos5.h

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 65dd599..88e8833 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -609,6 +609,12 @@ config I2C_S3C2410
          Say Y here to include support for I2C controller in the
          Samsung SoCs.
 
+config I2C_EXYNOS5
+       tristate "Exynos5 HS-I2C Driver"
+       help
+         Say Y here to include support for High Speed I2C controller in the
+         Exynos5 series SoCs from Samsung.
+
 config I2C_S6000
        tristate "S6000 I2C support"
        depends on XTENSA_VARIANT_S6000
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 2d33d62..426b4fd 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -60,6 +60,7 @@ 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_S3C2410)      += i2c-s3c2410.o
+obj-$(CONFIG_I2C_EXYNOS5)      += i2c-exynos5.o
 obj-$(CONFIG_I2C_S6000)                += i2c-s6000.o
 obj-$(CONFIG_I2C_SH7760)       += i2c-sh7760.o
 obj-$(CONFIG_I2C_SH_MOBILE)    += i2c-sh_mobile.o
diff --git a/drivers/i2c/busses/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c
new file mode 100644
index 0000000..5983aa9
--- /dev/null
+++ b/drivers/i2c/busses/i2c-exynos5.c
@@ -0,0 +1,758 @@
+/* linux/drivers/i2c/busses/i2c-exynos5.c
+ *
+ * Copyright (C) 2012 Samsung Electronics Co., Ltd.
+ *
+ * Exynos5 series High Speed I2C controller driver
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/of_i2c.h>
+#include <linux/of_gpio.h>
+
+#include <asm/irq.h>
+#include "i2c-exynos5.h"
+
+#define HSI2C_POLLING 0
+#define HSI2C_FAST_SPD 0
+#define HSI2C_HIGH_SPD 1
+
+/* Max time to wait for bus to become idle after a xfer */
+#define EXYNOS5_I2C_TIMEOUT (msecs_to_jiffies(1000))
+
+struct exynos5_i2c {
+       unsigned int            suspended:1;
+
+       struct i2c_msg          *msg;
+       struct completion       msg_complete;
+       unsigned int            msg_byte_ptr;
+
+       unsigned int            irq;
+
+       void __iomem            *regs;
+       struct clk              *clk;
+       struct device           *dev;
+       struct resource         *ioarea;
+       struct i2c_adapter      adap;
+       unsigned int            bus_number;
+       unsigned int            speed_mode;
+       unsigned int            fast_speed;
+       unsigned int            high_speed;
+       int                     operation_mode;
+       int                     gpios[2];
+};
+
+static struct platform_device_id exynos5_driver_ids[] = {
+       {
+               .name           = "exynos5-hs-i2c",
+               .driver_data    = 0,
+       }, { },
+};
+MODULE_DEVICE_TABLE(platform, exynos5_driver_ids);
+
+#ifdef CONFIG_OF
+static const struct of_device_id exynos5_i2c_match[] = {
+       { .compatible = "samsung,exynos5-hs-i2c", .data = (void *)0 },
+       {},
+};
+MODULE_DEVICE_TABLE(of, exynos5_i2c_match);
+#endif
+
+static inline void dump_i2c_register(struct exynos5_i2c *i2c)
+{
+       dev_dbg(i2c->dev, "Register dump(%d) :\n %x\n %x\n %x\n %x\n"
+               " %x\n %x\n %x\n %x\n %x\n"
+               " %x\n %x\n %x\n %x\n %x\n"
+               " %x\n %x\n %x\n %x\n %x\n"
+               " %x\n %x\n %x\n %x\n %x\n"
+               , i2c->suspended
+               , readl(i2c->regs + HSI2C_CTL)
+               , readl(i2c->regs + HSI2C_FIFO_CTL)
+               , readl(i2c->regs + HSI2C_TRAILIG_CTL)
+               , readl(i2c->regs + HSI2C_CLK_CTL)
+               , readl(i2c->regs + HSI2C_CLK_SLOT)
+               , readl(i2c->regs + HSI2C_INT_ENABLE)
+               , readl(i2c->regs + HSI2C_INT_STATUS)
+               , readl(i2c->regs + HSI2C_ERR_STATUS)
+               , readl(i2c->regs + HSI2C_FIFO_STATUS)
+               , readl(i2c->regs + HSI2C_TX_DATA)
+               , readl(i2c->regs + HSI2C_RX_DATA)
+               , readl(i2c->regs + HSI2C_CONF)
+               , readl(i2c->regs + HSI2C_AUTO_CONFING)
+               , readl(i2c->regs + HSI2C_TIMEOUT)
+               , readl(i2c->regs + HSI2C_MANUAL_CMD)
+               , readl(i2c->regs + HSI2C_TRANS_STATUS)
+               , readl(i2c->regs + HSI2C_TIMING_HS1)
+               , readl(i2c->regs + HSI2C_TIMING_HS2)
+               , readl(i2c->regs + HSI2C_TIMING_HS3)
+               , readl(i2c->regs + HSI2C_TIMING_FS1)
+               , readl(i2c->regs + HSI2C_TIMING_FS2)
+               , readl(i2c->regs + HSI2C_TIMING_FS3)
+               , readl(i2c->regs + HSI2C_TIMING_SLA)
+               , readl(i2c->regs + HSI2C_ADDR));
+}
+
+static inline void exynos5_i2c_stop(struct exynos5_i2c *i2c)
+{
+       writel(0, i2c->regs + HSI2C_INT_ENABLE);
+
+       complete(&i2c->msg_complete);
+}
+
+static inline void exynos5_disable_irq(struct exynos5_i2c *i2c)
+{
+       unsigned long tmp = readl(i2c->regs + HSI2C_INT_STATUS);
+
+       writel(tmp, i2c->regs +  HSI2C_INT_STATUS);
+}
+
+static void exynos5_i2c_en_timeout(struct exynos5_i2c *i2c)
+{
+       unsigned long i2c_timeout = readl(i2c->regs + HSI2C_TIMEOUT);
+
+       /* Clear to enable Timeout */
+       i2c_timeout &= ~HSI2C_TIMEOUT_EN;
+       writel(i2c_timeout, i2c->regs + HSI2C_TIMEOUT);
+}
+
+static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id)
+{
+       struct exynos5_i2c *i2c = dev_id;
+       unsigned char byte;
+
+       if (i2c->msg->flags & I2C_M_RD) {
+               while ((readl(i2c->regs + HSI2C_FIFO_STATUS) &
+                       0x1000000) == 0) {
+                       byte = (unsigned char)readl(i2c->regs + HSI2C_RX_DATA);
+                       i2c->msg->buf[i2c->msg_byte_ptr++] = byte;
+               }
+
+               if (i2c->msg_byte_ptr >= i2c->msg->len)
+                       exynos5_i2c_stop(i2c);
+       } else {
+               byte = i2c->msg->buf[i2c->msg_byte_ptr++];
+               writel(byte, i2c->regs + HSI2C_TX_DATA);
+
+               if (i2c->msg_byte_ptr >= i2c->msg->len)
+                       exynos5_i2c_stop(i2c);
+       }
+
+       exynos5_disable_irq(i2c);
+
+       return IRQ_HANDLED;
+}
+
+static int exynos5_i2c_init(struct exynos5_i2c *i2c);
+
+static int exynos5_i2c_reset(struct exynos5_i2c *i2c)
+{
+       unsigned long usi_ctl;
+
+       usi_ctl = readl(i2c->regs + HSI2C_CTL);
+       usi_ctl |= (1u << 31);
+       writel(usi_ctl, i2c->regs + HSI2C_CTL);
+       usi_ctl = readl(i2c->regs + HSI2C_CTL);
+       usi_ctl &= ~(1u << 31);
+       writel(usi_ctl, i2c->regs + HSI2C_CTL);
+       exynos5_i2c_init(i2c);
+
+       return 0;
+}
+
+static int exynos5_i2c_xfer_msg(struct exynos5_i2c *i2c,
+                             struct i2c_msg *msgs, int num, int stop)
+{
+       unsigned long timeout;
+       unsigned long trans_status;
+       unsigned long usi_fifo_stat;
+       unsigned long usi_ctl;
+       unsigned long i2c_auto_conf;
+       unsigned long i2c_addr;
+       unsigned long usi_int_en;
+       unsigned long usi_fifo_ctl;
+       unsigned char byte;
+       int ret = 0;
+       int operation_mode = i2c->operation_mode;
+
+       i2c->msg = msgs;
+       i2c->msg_byte_ptr = 0;
+
+       init_completion(&i2c->msg_complete);
+
+       usi_ctl         = readl(i2c->regs + HSI2C_CTL);
+       i2c_auto_conf   = readl(i2c->regs + HSI2C_AUTO_CONFING);
+
+       exynos5_i2c_en_timeout(i2c);
+
+       /* Set default trigger level for TXFIFO and RXFIFO */
+       usi_fifo_ctl = HSI2C_TXFIFO_TRIGGER_LEVEL |
+                                       HSI2C_RXFIFO_TRIGGER_LEVEL;
+       /* Enable RXFIFO and TXFIFO */
+       usi_fifo_ctl = HSI2C_RXFIFO_EN | HSI2C_TXFIFO_EN;
+
+       writel(usi_fifo_ctl, i2c->regs + HSI2C_FIFO_CTL);
+
+       usi_int_en = 0;
+       if (msgs->flags & I2C_M_RD) {
+               usi_ctl &= ~HSI2C_TXCHON;
+               usi_ctl |= HSI2C_RXCHON;
+
+               i2c_auto_conf |= HSI2C_READ_WRITE;
+
+               usi_int_en |= (HSI2C_INT_RX_ALMOSTFULL_EN |
+                                       HSI2C_INT_TRAILING_EN);
+       } else {
+               usi_ctl &= ~HSI2C_RXCHON;
+               usi_ctl |= HSI2C_TXCHON;
+
+               i2c_auto_conf &= ~HSI2C_READ_WRITE;
+
+               usi_int_en |= HSI2C_INT_TX_ALMOSTEMPTY_EN;
+       }
+
+       if (stop == 1)
+               i2c_auto_conf |= HSI2C_STOP_AFTER_TRANS;
+       else
+               i2c_auto_conf &= ~HSI2C_STOP_AFTER_TRANS;
+
+
+       i2c_addr = readl(i2c->regs + HSI2C_ADDR);
+
+       /* Clear Slave Address for I2C Master (Auto mode only) */
+       i2c_addr &= ~(0x3ff << 10);
+       /* Clear Slave Address for I2C Slave */
+       i2c_addr &= ~(0x3ff << 0);
+       /* Clear Master ID for I2C Master (Auto and HS mode only) */
+       if (i2c->speed_mode == HSI2C_HIGH_SPD)
+               i2c_addr &= ~(0xff << 24);
+
+       i2c_addr |= ((msgs->addr & 0x7f) << 10);
+       writel(i2c_addr, i2c->regs + HSI2C_ADDR);
+
+       writel(usi_ctl, i2c->regs + HSI2C_CTL);
+
+       /* Clear and set TRANS_LEN */
+       i2c_auto_conf &= ~(0xffff);
+       i2c_auto_conf |= i2c->msg->len;
+       writel(i2c_auto_conf, i2c->regs + HSI2C_AUTO_CONFING);
+
+       /* Start data transfer in Master mode */
+       i2c_auto_conf = readl(i2c->regs + HSI2C_AUTO_CONFING);
+       i2c_auto_conf |= HSI2C_MASTER_RUN;
+       writel(i2c_auto_conf, i2c->regs + HSI2C_AUTO_CONFING);
+
+       /* Enable appropriate interrupts */
+       if (operation_mode != HSI2C_POLLING)
+               writel(usi_int_en, i2c->regs + HSI2C_INT_ENABLE);
+
+       ret = -EAGAIN;
+       if (msgs->flags & I2C_M_RD) {
+               if (operation_mode == HSI2C_POLLING) {
+                       timeout = jiffies + EXYNOS5_I2C_TIMEOUT;
+                       while (time_before(jiffies, timeout)) {
+                               if ((readl(i2c->regs + HSI2C_FIFO_STATUS) &
+                                       0x1000000) == 0) {
+                                       byte = (unsigned char)readl
+                                               (i2c->regs + HSI2C_RX_DATA);
+                                       i2c->msg->buf[i2c->msg_byte_ptr++]
+                                               = byte;
+                               }
+
+                               if (i2c->msg_byte_ptr >= i2c->msg->len) {
+                                       ret = 0;
+                                       break;
+                               }
+                       }
+
+                       if (ret == -EAGAIN) {
+                               exynos5_i2c_reset(i2c);
+                               dev_warn(i2c->dev, "rx timeout\n");
+                               return ret;
+                       }
+               } else {
+                       timeout = wait_for_completion_interruptible_timeout
+                               (&i2c->msg_complete, EXYNOS5_I2C_TIMEOUT);
+
+                       if (timeout == 0) {
+                               exynos5_i2c_reset(i2c);
+                               dev_warn(i2c->dev, "rx timeout\n");
+                               return ret;
+                       }
+
+                       ret = 0;
+               }
+       } else {
+               if (operation_mode == HSI2C_POLLING) {
+                       timeout = jiffies + EXYNOS5_I2C_TIMEOUT;
+                       while (time_before(jiffies, timeout) &&
+                               (i2c->msg_byte_ptr < i2c->msg->len)) {
+                               if ((readl(i2c->regs + HSI2C_FIFO_STATUS)
+                                       & 0x7f) < 64) {
+                                       byte = i2c->msg->buf
+                                               [i2c->msg_byte_ptr++];
+                                       writel(byte,
+                                               i2c->regs + HSI2C_TX_DATA);
+                               }
+                       }
+               } else {
+                       timeout = wait_for_completion_interruptible_timeout
+                               (&i2c->msg_complete, EXYNOS5_I2C_TIMEOUT);
+
+                       if (timeout == 0) {
+                               exynos5_i2c_reset(i2c);
+                               dev_warn(i2c->dev, "tx timeout\n");
+                               return ret;
+                       }
+
+                       timeout = jiffies + timeout;
+               }
+               while (time_before(jiffies, timeout)) {
+                       usi_fifo_stat = readl(i2c->regs + HSI2C_FIFO_STATUS);
+                       trans_status = readl(i2c->regs + HSI2C_TRANS_STATUS);
+                       if ((usi_fifo_stat == HSI2C_FIFO_EMPTY) &&
+                               ((trans_status == 0) ||
+                               ((stop == 0) &&
+                               (trans_status == 0x20000)))) {
+                               ret = 0;
+                               break;
+                       }
+               }
+               if (ret == -EAGAIN) {
+                       exynos5_i2c_reset(i2c);
+                       dev_warn(i2c->dev, "tx timeout\n");
+                       return ret;
+               }
+       }
+
+       return ret;
+}
+
+static int exynos5_i2c_xfer(struct i2c_adapter *adap,
+                       struct i2c_msg *msgs, int num)
+{
+       struct exynos5_i2c *i2c = (struct exynos5_i2c *)adap->algo_data;
+       int retry, i;
+       int ret;
+       int stop = 0;
+       struct i2c_msg *msgs_ptr = msgs;
+
+       if (i2c->suspended) {
+               dev_err(i2c->dev, "HS-I2C is not initialzed.\n");
+               return -EIO;
+       }
+
+       clk_prepare_enable(i2c->clk);
+
+       for (retry = 0; retry < adap->retries; retry++) {
+               for (i = 0; i < num; i++) {
+                       if (i == num - 1)
+                               stop = 1;
+                       ret = exynos5_i2c_xfer_msg(i2c, msgs_ptr, 1, stop);
+                       msgs_ptr++;
+
+                       if (ret == -EAGAIN) {
+                               msgs_ptr = msgs;
+                               stop = 0;
+                               break;
+                       }
+               }
+               if (i == num) {
+                       clk_disable_unprepare(i2c->clk);
+                       return num;
+               }
+
+               dev_dbg(i2c->dev, "retrying transfer (%d)\n", retry);
+
+               udelay(100);
+       }
+
+       clk_disable_unprepare(i2c->clk);
+
+       return -EREMOTEIO;
+}
+
+static u32 exynos5_i2c_func(struct i2c_adapter *adap)
+{
+       return I2C_FUNC_I2C;
+}
+
+static const struct i2c_algorithm exynos5_i2c_algorithm = {
+       .master_xfer            = exynos5_i2c_xfer,
+       .functionality          = exynos5_i2c_func,
+};
+
+static int exynos5_i2c_set_timing(struct exynos5_i2c *i2c)
+{
+       unsigned long i2c_timing_s1;
+       unsigned long i2c_timing_s2;
+       unsigned long i2c_timing_s3;
+       unsigned long i2c_timing_sla;
+       unsigned int op_clk;
+       unsigned int clkin = clk_get_rate(i2c->clk);
+       unsigned int n_clkdiv;
+       unsigned int t_start_su, t_start_hd;
+       unsigned int t_stop_su;
+       unsigned int t_data_su, t_data_hd;
+       unsigned int t_scl_l, t_scl_h;
+       unsigned int t_sr_release;
+       unsigned int t_ftl_cycle;
+       unsigned int i = 0, utemp0 = 0, utemp1 = 0, utemp2 = 0;
+
+       if (i2c->speed_mode == HSI2C_HIGH_SPD)
+               op_clk = i2c->high_speed;
+       else
+               op_clk = i2c->fast_speed;
+
+       /* FPCLK / FI2C =
+        * (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2) + 8 + 2 * FLT_CYCLE
+        * uTemp0 = (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2)
+        * uTemp1 = (TSCLK_L + TSCLK_H + 2)
+        * uTemp2 = TSCLK_L + TSCLK_H
+       */
+       t_ftl_cycle = (readl(i2c->regs + HSI2C_CONF) >> 16) & 0x7;
+       utemp0 = (clkin / op_clk) - 8 - 2 * t_ftl_cycle;
+
+       /* CLK_DIV max is 256 */
+       for (i = 0; i < 256; i++) {
+               utemp1 = utemp0 / (i + 1);
+               /* SCLK_L/H max is 256 / 2 */
+               if (utemp1 < 128) {
+                       utemp2 = utemp1 - 2;
+                       break;
+               }
+       }
+
+       n_clkdiv = i;
+       t_scl_l = utemp2 / 2;
+       t_scl_h = utemp2 / 2;
+       t_start_su = t_scl_l;
+       t_start_hd = t_scl_l;
+       t_stop_su = t_scl_l;
+       t_data_su = t_scl_l / 2;
+       t_data_hd = t_scl_l / 2;
+       t_sr_release = utemp2;
+
+       i2c_timing_s1 = t_start_su << 24 | t_start_hd << 16 | t_stop_su << 8;
+       i2c_timing_s2 = t_data_su << 24 | t_scl_l << 8 | t_scl_h << 0;
+       i2c_timing_s3 = n_clkdiv << 16 | t_sr_release << 0;
+       i2c_timing_sla = t_data_hd << 0;
+
+       dev_dbg(i2c->dev, "tSTART_SU: %X, tSTART_HD: %X, tSTOP_SU: %X\n",
+               t_start_su, t_start_hd, t_stop_su);
+       dev_dbg(i2c->dev, "tDATA_SU: %X, tSCL_L: %X, tSCL_H: %X\n",
+               t_data_su, t_scl_l, t_scl_h);
+       dev_dbg(i2c->dev, "nClkDiv: %X, tSR_RELEASE: %X\n",
+               n_clkdiv, t_sr_release);
+       dev_dbg(i2c->dev, "tDATA_HD: %X\n", t_data_hd);
+
+       if (i2c->speed_mode == HSI2C_HIGH_SPD) {
+               writel(i2c_timing_s1, i2c->regs + HSI2C_TIMING_HS1);
+               writel(i2c_timing_s2, i2c->regs + HSI2C_TIMING_HS2);
+               writel(i2c_timing_s3, i2c->regs + HSI2C_TIMING_HS3);
+       } else {
+               writel(i2c_timing_s1, i2c->regs + HSI2C_TIMING_FS1);
+               writel(i2c_timing_s2, i2c->regs + HSI2C_TIMING_FS2);
+               writel(i2c_timing_s3, i2c->regs + HSI2C_TIMING_FS3);
+       }
+       writel(i2c_timing_sla, i2c->regs + HSI2C_TIMING_SLA);
+
+       return 0;
+}
+
+#ifdef CONFIG_OF
+static int exynos5_i2c_parse_dt_gpio(struct exynos5_i2c *i2c)
+{
+       int idx, gpio, ret;
+
+       for (idx = 0; idx < 2; idx++) {
+               gpio = of_get_gpio(i2c->dev->of_node, idx);
+               if (!gpio_is_valid(gpio)) {
+                       dev_err(i2c->dev, "invalid gpio[%d]: %d\n", idx, gpio);
+                       goto free_gpio;
+               }
+               i2c->gpios[idx] = gpio;
+
+               ret = gpio_request(gpio, "hsi2c-bus");
+               if (ret) {
+                       dev_err(i2c->dev, "gpio [%d] request failed\n", gpio);
+                       goto free_gpio;
+               }
+       }
+       return 0;
+
+free_gpio:
+       while (--idx >= 0)
+               gpio_free(i2c->gpios[idx]);
+       return -EINVAL;
+}
+
+static void exynos5_i2c_dt_gpio_free(struct exynos5_i2c *i2c)
+{
+       unsigned int idx;
+
+       for (idx = 0; idx < 2; idx++)
+               gpio_free(i2c->gpios[idx]);
+}
+#else
+static int exynos5_i2c_parse_dt_gpio(struct exynos5_i2c *i2c)
+{
+       return 0;
+}
+
+static void exynos5_i2c_dt_gpio_free(struct exynos5_i2c *i2c)
+{
+}
+#endif
+
+static int exynos5_i2c_init(struct exynos5_i2c *i2c)
+{
+       unsigned long usi_ctl = HSI2C_FUNC_MODE_I2C | HSI2C_MASTER;
+       unsigned long usi_trailing_ctl = HSI2C_TRAILING_COUNT;
+       unsigned long i2c_conf = readl(i2c->regs + HSI2C_CONF);
+
+       if (exynos5_i2c_parse_dt_gpio(i2c))
+               return -EINVAL;
+
+       writel(usi_ctl, i2c->regs + HSI2C_CTL);
+
+       writel(usi_trailing_ctl, i2c->regs + HSI2C_TRAILIG_CTL);
+
+       exynos5_i2c_set_timing(i2c);
+
+       if (i2c->speed_mode == HSI2C_HIGH_SPD) {
+               i2c_conf |= HSI2C_HS_MODE;
+               writel(i2c_conf, i2c->regs + HSI2C_CONF);
+       }
+
+       return 0;
+}
+
+static int exynos5_i2c_probe(struct platform_device *pdev)
+{
+       struct exynos5_i2c *i2c;
+       struct resource *res;
+       int ret;
+
+       i2c = devm_kzalloc(&pdev->dev, sizeof(struct exynos5_i2c), GFP_KERNEL);
+       if (!i2c) {
+               dev_err(&pdev->dev, "no memory for state\n");
+               return -ENOMEM;
+       }
+
+       if (pdev->dev.of_node) {
+               /* i2c bus number is dynamically assigned */
+               i2c->bus_number = -1;
+
+               if (of_property_read_u32(pdev->dev.of_node,
+                               "samsung,hsi2c-speed-mode", &i2c->speed_mode))
+                       i2c->speed_mode = 1;
+               if (!of_property_read_u32(pdev->dev.of_node,
+                               "samsung,hsi2c-hs-clk", &i2c->high_speed))
+                       i2c->high_speed = 2500000;
+               if (!of_property_read_u32(pdev->dev.of_node,
+                               "samsung,hsi2c-fs-clk", &i2c->fast_speed))
+                       i2c->fast_speed = 400000;
+       } else {
+               dev_err(&pdev->dev, "no device node\n");
+               return -ENOENT;
+       }
+
+       strlcpy(i2c->adap.name, "exynos5250-i2c", sizeof(i2c->adap.name));
+       i2c->adap.owner   = THIS_MODULE;
+       i2c->adap.algo    = &exynos5_i2c_algorithm;
+       i2c->adap.retries = 2;
+       i2c->adap.class   = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+
+       i2c->dev = &pdev->dev;
+       i2c->clk = clk_get(&pdev->dev, "hsi2c");
+       if (IS_ERR(i2c->clk)) {
+               dev_err(&pdev->dev, "cannot get clock\n");
+               ret = -ENOENT;
+               goto err_noclk;
+       }
+
+       clk_prepare_enable(i2c->clk);
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (res == NULL) {
+               dev_err(&pdev->dev, "cannot find HS-I2C IO resource\n");
+               ret = -ENOENT;
+               goto err_clk;
+       }
+
+       i2c->ioarea = request_mem_region(res->start, resource_size(res),
+                                        pdev->name);
+
+       if (i2c->ioarea == NULL) {
+               dev_err(&pdev->dev, "cannot request HS-I2C IO\n");
+               ret = -ENXIO;
+               goto err_clk;
+       }
+
+       i2c->regs = ioremap(res->start, resource_size(res));
+
+       if (i2c->regs == NULL) {
+               dev_err(&pdev->dev, "cannot map HS-I2C IO\n");
+               ret = -ENXIO;
+               goto err_ioarea;
+       }
+
+       dev_dbg(&pdev->dev, "registers %p (%p, %p)\n",
+               i2c->regs, i2c->ioarea, res);
+
+       i2c->adap.algo_data = i2c;
+       i2c->adap.dev.parent = &pdev->dev;
+
+       ret = exynos5_i2c_init(i2c);
+       if (ret != 0)
+               goto err_iomap;
+
+       i2c->irq = ret = platform_get_irq(pdev, 0);
+       if (ret <= 0) {
+               dev_err(&pdev->dev, "cannot find HS-I2C IRQ\n");
+               goto err_iomap;
+       }
+
+       ret = request_irq(i2c->irq, exynos5_i2c_irq, IRQF_DISABLED,
+                         dev_name(&pdev->dev), i2c);
+
+       if (ret != 0) {
+               dev_err(&pdev->dev, "cannot request HS-I2C IRQ %d\n", i2c->irq);
+               goto err_iomap;
+       }
+
+       i2c->adap.nr = i2c->bus_number;
+       i2c->adap.dev.of_node = pdev->dev.of_node;
+
+       ret = i2c_add_numbered_adapter(&i2c->adap);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "failed to add bus to i2c core\n");
+               goto err_irq;
+       }
+
+       of_i2c_register_devices(&i2c->adap);
+       platform_set_drvdata(pdev, i2c);
+
+       dev_info(&pdev->dev, "%s: Exynos5 HS-I2C adapter\n",
+               dev_name(&i2c->adap.dev));
+       clk_disable_unprepare(i2c->clk);
+       return 0;
+
+ err_irq:
+       free_irq(i2c->irq, i2c);
+
+ err_iomap:
+       iounmap(i2c->regs);
+
+ err_ioarea:
+       release_resource(i2c->ioarea);
+       kfree(i2c->ioarea);
+
+ err_clk:
+       clk_disable_unprepare(i2c->clk);
+       clk_put(i2c->clk);
+
+ err_noclk:
+       return ret;
+}
+
+static int exynos5_i2c_remove(struct platform_device *pdev)
+{
+       struct exynos5_i2c *i2c = platform_get_drvdata(pdev);
+
+       i2c_del_adapter(&i2c->adap);
+       free_irq(i2c->irq, i2c);
+
+       clk_disable_unprepare(i2c->clk);
+       clk_put(i2c->clk);
+
+       iounmap(i2c->regs);
+
+       release_resource(i2c->ioarea);
+       exynos5_i2c_dt_gpio_free(i2c);
+       kfree(i2c->ioarea);
+
+       return 0;
+}
+
+#ifdef CONFIG_PM
+static int exynos5_i2c_suspend_noirq(struct device *dev)
+{
+       struct platform_device *pdev = to_platform_device(dev);
+       struct exynos5_i2c *i2c = platform_get_drvdata(pdev);
+
+       i2c_lock_adapter(&i2c->adap);
+       i2c->suspended = 1;
+       i2c_unlock_adapter(&i2c->adap);
+
+       return 0;
+}
+
+static int exynos5_i2c_resume(struct device *dev)
+{
+       struct platform_device *pdev = to_platform_device(dev);
+       struct exynos5_i2c *i2c = platform_get_drvdata(pdev);
+
+       i2c_lock_adapter(&i2c->adap);
+       clk_prepare_enable(i2c->clk);
+       exynos5_i2c_init(i2c);
+       clk_disable_unprepare(i2c->clk);
+       i2c->suspended = 0;
+       i2c_unlock_adapter(&i2c->adap);
+
+       return 0;
+}
+
+static const struct dev_pm_ops exynos5_i2c_dev_pm_ops = {
+       .suspend_noirq  = exynos5_i2c_suspend_noirq,
+       .resume_noirq   = exynos5_i2c_resume,
+};
+
+#define EXYNOS5_DEV_PM_OPS (&exynos5_i2c_dev_pm_ops)
+#else
+#define EXYNOS5_DEV_PM_OPS NULL
+#endif
+
+static struct platform_driver exynos5_i2c_driver = {
+       .probe          = exynos5_i2c_probe,
+       .remove         = exynos5_i2c_remove,
+       .id_table       = exynos5_driver_ids,
+       .driver         = {
+               .owner  = THIS_MODULE,
+               .name   = "exynos5-i2c",
+               .pm     = EXYNOS5_DEV_PM_OPS,
+               .of_match_table = of_match_ptr(exynos5_i2c_match),
+       },
+};
+
+static int __init i2c_adap_exynos5_init(void)
+{
+       return platform_driver_register(&exynos5_i2c_driver);
+}
+subsys_initcall(i2c_adap_exynos5_init);
+
+static void __exit i2c_adap_exynos5_exit(void)
+{
+       platform_driver_unregister(&exynos5_i2c_driver);
+}
+module_exit(i2c_adap_exynos5_exit);
+
+MODULE_DESCRIPTION("Exynos5 HS-I2C Bus driver");
+MODULE_AUTHOR("Taekgyun Ko, <taeggyun...@samsung.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/i2c/busses/i2c-exynos5.h b/drivers/i2c/busses/i2c-exynos5.h
new file mode 100644
index 0000000..063051e
--- /dev/null
+++ b/drivers/i2c/busses/i2c-exynos5.h
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2012 Samsung Electronics Co., Ltd.
+ *
+ * Exynos5 series HS-I2C Controller
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#ifndef __ASM_ARCH_REGS_HS_IIC_H
+#define __ASM_ARCH_REGS_HS_IIC_H __FILE__
+
+/*
+ *     Register Map
+ */
+#define HSI2C_CTL                              0x00
+#define HSI2C_FIFO_CTL                         0x04
+#define HSI2C_TRAILIG_CTL                      0x08
+#define HSI2C_CLK_CTL                          0x0C
+#define HSI2C_CLK_SLOT                         0x10
+#define HSI2C_INT_ENABLE                       0x20
+#define HSI2C_INT_STATUS                       0x24
+#define HSI2C_ERR_STATUS                       0x2C
+#define HSI2C_FIFO_STATUS                      0x30
+#define HSI2C_TX_DATA                          0x34
+#define HSI2C_RX_DATA                          0x38
+#define HSI2C_CONF                             0x40
+#define HSI2C_AUTO_CONFING                     0x44
+#define HSI2C_TIMEOUT                          0x48
+#define HSI2C_MANUAL_CMD                       0x4C
+#define HSI2C_TRANS_STATUS                     0x50
+#define HSI2C_TIMING_HS1                       0x54
+#define HSI2C_TIMING_HS2                       0x58
+#define HSI2C_TIMING_HS3                       0x5C
+#define HSI2C_TIMING_FS1                       0x60
+#define HSI2C_TIMING_FS2                       0x64
+#define HSI2C_TIMING_FS3                       0x68
+#define HSI2C_TIMING_SLA                       0x6C
+#define HSI2C_ADDR                             0x70
+
+/* I2C_CTL Register */
+#define HSI2C_FUNC_MODE_I2C                    (1u << 0)
+#define HSI2C_MASTER                           (1u << 3)
+#define HSI2C_RXCHON                           (1u << 6)
+#define HSI2C_TXCHON                           (1u << 7)
+
+/* I2C_FIFO_CTL Register */
+#define HSI2C_RXFIFO_EN                                (1u << 0)
+#define HSI2C_TXFIFO_EN                                (1u << 1)
+#define HSI2C_TXFIFO_TRIGGER_LEVEL             (0x20 << 16)
+#define HSI2C_RXFIFO_TRIGGER_LEVEL             (0x20 << 4)
+
+/* I2C_TRAILING_CTL Register */
+#define HSI2C_TRAILING_COUNT                   (0xf)
+
+/* I2C_INT_EN Register */
+#define HSI2C_INT_TX_ALMOSTEMPTY_EN            (1u << 0) /* For TX FIFO */
+#define HSI2C_INT_RX_ALMOSTFULL_EN             (1u << 1) /* For RX FIFO */
+#define HSI2C_INT_TRAILING_EN                  (1u << 6)
+
+/* I2C_CONF Register */
+#define HSI2C_AUTO_MODE                                (1u << 31)
+#define HSI2C_10BIT_ADDR_MODE                  (1u << 30)
+#define HSI2C_HS_MODE                          (1u << 29)
+
+/* I2C_AUTO_CONF Register */
+#define HSI2C_READ_WRITE                       (1u << 16)
+#define HSI2C_STOP_AFTER_TRANS                 (1u << 17)
+#define HSI2C_MASTER_RUN                       (1u << 31)
+
+/* I2C_TIMEOUT Register */
+#define HSI2C_TIMEOUT_EN                       (1u << 31)
+
+#define HSI2C_FIFO_EMPTY                       (0x1000100)
+
+#define HSI2C_FS_BPS                           400000
+#define HSI2C_HS_BPS                           2500000
+
+#endif /* __ASM_ARCH_REGS_HS_IIC_H */
-- 
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to