| /* linux/drivers/i2c/busses/i2c-s3c2410.c |
| * |
| * Copyright (C) 2004,2005,2009 Simtec Electronics |
| * Ben Dooks <ben@simtec.co.uk> |
| * |
| * S3C2410 I2C Controller |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * 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/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/pm_runtime.h> |
| #include <linux/clk.h> |
| #include <linux/slab.h> |
| #include <linux/io.h> |
| #include <linux/of.h> |
| #include <linux/of_gpio.h> |
| #include <linux/pinctrl/consumer.h> |
| #include "../../pinctrl/core.h" |
| |
| #include <asm/irq.h> |
| |
| #include <linux/platform_data/i2c-s3c2410.h> |
| |
| #ifdef CONFIG_CPU_IDLE |
| #include <soc/samsung/exynos-pm.h> |
| static LIST_HEAD(drvdata_list); |
| #endif |
| |
| /* see s3c2410x user guide, v1.1, section 9 (p447) for more info */ |
| |
| #define S3C2410_IICCON 0x00 |
| #define S3C2410_IICSTAT 0x04 |
| #define S3C2410_IICADD 0x08 |
| #define S3C2410_IICDS 0x0C |
| #define S3C2440_IICLC 0x10 |
| #define S3C2440_CLK_BYPASS 0x14 |
| #define S3C2440_IICINT 0x20 |
| #define S3C2440_IICNCLK_DIV2 0x28 |
| |
| #define S3C2410_IICCON_BUSHOLD_IRQEN (1 << 8) |
| #define S3C2410_IICCON_ACKEN (1 << 7) |
| #define S3C2410_IICCON_TXDIV_16 (0 << 6) |
| #define S3C2410_IICCON_TXDIV_512 (1 << 6) |
| #define S3C2410_IICCON_IRQEN (1 << 5) |
| #define S3C2410_IICCON_IRQPEND (1 << 4) |
| #define S3C2410_IICCON_BUS_RELEASE (1 << 4) |
| #define S3C2410_IICCON_SCALE(x) ((x) & 0xf) |
| #define S3C2410_IICCON_SCALEMASK (0xf) |
| |
| #define S3C2410_IICSTAT_MASTER_RX (2 << 6) |
| #define S3C2410_IICSTAT_MASTER_TX (3 << 6) |
| #define S3C2410_IICSTAT_SLAVE_RX (0 << 6) |
| #define S3C2410_IICSTAT_SLAVE_TX (1 << 6) |
| #define S3C2410_IICSTAT_MODEMASK (3 << 6) |
| |
| #define S3C2410_IICSTAT_START (1 << 5) |
| #define S3C2410_IICSTAT_BUSBUSY (1 << 5) |
| #define S3C2410_IICSTAT_TXRXEN (1 << 4) |
| #define S3C2410_IICSTAT_ARBITR (1 << 3) |
| #define S3C2410_IICSTAT_ASSLAVE (1 << 2) |
| #define S3C2410_IICSTAT_ADDR0 (1 << 1) |
| #define S3C2410_IICSTAT_LASTBIT (1 << 0) |
| |
| #define S3C2410_IICLC_SDA_DELAY0 (0 << 0) |
| #define S3C2410_IICLC_SDA_DELAY5 (1 << 0) |
| #define S3C2410_IICLC_SDA_DELAY10 (2 << 0) |
| #define S3C2410_IICLC_SDA_DELAY15 (3 << 0) |
| #define S3C2410_IICLC_SDA_DELAY_MASK (3 << 0) |
| |
| #define S3C2410_IICLC_FILTER_ON (1 << 2) |
| |
| #define S3C2440_IICINT_BUSHOLD_CLEAR (1 << 8) |
| |
| #define S3C2410_NEED_REG_INIT (1 << 0) |
| #define S3C2410_NEED_BUS_INIT (2 << 0) |
| #define S3C2410_NEED_FULL_INIT (3 << 0) |
| |
| /* Treat S3C2410 as baseline hardware, anything else is supported via quirks */ |
| #define QUIRK_S3C2440 (1 << 0) |
| #define QUIRK_HDMIPHY (1 << 1) |
| #define QUIRK_NO_GPIO (1 << 2) |
| #define QUIRK_POLL (1 << 3) |
| #define QUIRK_FIMC_I2C (1 << 4) |
| |
| /* Max time to wait for bus to become idle after a xfer (in us) */ |
| #define S3C2410_IDLE_TIMEOUT 5000 |
| |
| /* i2c controller state */ |
| enum s3c24xx_i2c_state { |
| STATE_IDLE, |
| STATE_START, |
| STATE_READ, |
| STATE_WRITE, |
| STATE_STOP |
| }; |
| |
| struct s3c24xx_i2c { |
| struct list_head node; |
| wait_queue_head_t wait; |
| kernel_ulong_t quirks; |
| unsigned int need_hw_init; |
| unsigned int suspended:1; |
| |
| struct i2c_msg *msg; |
| unsigned int msg_num; |
| unsigned int msg_idx; |
| unsigned int msg_ptr; |
| |
| unsigned int tx_setup; |
| unsigned int irq; |
| |
| |
| enum s3c24xx_i2c_state state; |
| unsigned long clkrate; |
| |
| void __iomem *regs; |
| struct clk *rate_clk; |
| struct clk *clk; |
| struct device *dev; |
| struct i2c_adapter adap; |
| |
| struct s3c2410_platform_i2c *pdata; |
| int gpios[2]; |
| struct pinctrl *pctrl; |
| int idle_ip_index; |
| int reset_before_trans; |
| int fix_doxfer_return; |
| int filter_on; |
| }; |
| |
| static const struct platform_device_id s3c24xx_driver_ids[] = { |
| { |
| .name = "s3c2410-i2c", |
| .driver_data = 0, |
| }, { |
| .name = "s3c2440-i2c", |
| .driver_data = QUIRK_S3C2440, |
| }, { |
| .name = "s3c2440-hdmiphy-i2c", |
| .driver_data = QUIRK_S3C2440 | QUIRK_HDMIPHY | QUIRK_NO_GPIO, |
| }, { |
| .name = "exynos5430-fimc-i2c", |
| .driver_data = QUIRK_S3C2440 | QUIRK_FIMC_I2C, |
| }, { }, |
| }; |
| MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids); |
| |
| static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat); |
| |
| #ifdef CONFIG_OF |
| static const struct of_device_id s3c24xx_i2c_match[] = { |
| { .compatible = "samsung,s3c2410-i2c", .data = (void *)0 }, |
| { .compatible = "samsung,s3c2440-i2c", .data = (void *)QUIRK_S3C2440 }, |
| { .compatible = "samsung,s3c2440-i2c-polling", .data = (void *)(QUIRK_S3C2440 | QUIRK_POLL) }, |
| { .compatible = "samsung,s3c2440-hdmiphy-i2c", |
| .data = (void *)(QUIRK_S3C2440 | QUIRK_HDMIPHY | QUIRK_NO_GPIO) }, |
| { .compatible = "samsung,exynos5430-fimc-i2c", |
| .data = (void *)(QUIRK_S3C2440 | QUIRK_FIMC_I2C) }, |
| { .compatible = "samsung,exynos5440-i2c", |
| .data = (void *)(QUIRK_S3C2440 | QUIRK_NO_GPIO) }, |
| { .compatible = "samsung,exynos5-sata-phy-i2c", |
| .data = (void *)(QUIRK_S3C2440 | QUIRK_POLL | QUIRK_NO_GPIO) }, |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(of, s3c24xx_i2c_match); |
| #endif |
| |
| static void recover_i2c_gpio(struct s3c24xx_i2c *i2c) |
| { |
| int gpio_sda, gpio_scl; |
| int sda_val, scl_val, clk_cnt; |
| unsigned long timeout; |
| struct device_node *np = i2c->dev->of_node; |
| struct pinctrl_state *default_i2c_pins; |
| struct pinctrl *default_i2c_pinctrl; |
| int status = 0; |
| |
| dev_err(i2c->dev, "Recover GPIO pins\n"); |
| |
| gpio_sda = of_get_named_gpio(np, "gpio_sda", 0); |
| if (!gpio_is_valid(gpio_sda)) { |
| dev_err(i2c->dev, "Can't get gpio_sda!!!\n"); |
| return ; |
| } |
| gpio_scl = of_get_named_gpio(np, "gpio_scl", 0); |
| if (!gpio_is_valid(gpio_scl)) { |
| dev_err(i2c->dev, "Can't get gpio_scl!!!\n"); |
| return ; |
| } |
| |
| sda_val = gpio_get_value(gpio_sda); |
| scl_val = gpio_get_value(gpio_scl); |
| |
| dev_err(i2c->dev, "SDA line : %s, SCL line : %s\n", |
| sda_val ? "HIGH" : "LOW", scl_val ? "HIGH" : "LOW"); |
| |
| if (sda_val == 1) |
| return ; |
| |
| /* Wait for SCL as high for 500msec */ |
| if (scl_val == 0) { |
| timeout = jiffies + msecs_to_jiffies(500); |
| while (time_before(jiffies, timeout)) { |
| if (gpio_get_value(gpio_scl) != 0) { |
| timeout = 0; |
| break; |
| } |
| msleep(10); |
| } |
| if (timeout) |
| dev_err(i2c->dev, "SCL line is still LOW!!!\n"); |
| } |
| |
| sda_val = gpio_get_value(gpio_sda); |
| |
| if (sda_val == 0) { |
| gpio_direction_output(gpio_scl, 1); |
| gpio_direction_input(gpio_sda); |
| |
| for (clk_cnt = 0; clk_cnt < 100; clk_cnt++) { |
| /* Make clock for slave */ |
| gpio_set_value(gpio_scl, 0); |
| udelay(5); |
| gpio_set_value(gpio_scl, 1); |
| udelay(5); |
| if (gpio_get_value(gpio_sda) == 1) { |
| dev_err(i2c->dev, "SDA line is recovered.\n"); |
| break; |
| } |
| } |
| if (clk_cnt == 100) |
| dev_err(i2c->dev, "SDA line is not recovered!!!\n"); |
| } |
| |
| default_i2c_pinctrl = devm_pinctrl_get(i2c->dev); |
| if (IS_ERR(default_i2c_pinctrl)) { |
| dev_err(i2c->dev, "Can't get i2c pinctrl!!!\n"); |
| return ; |
| } |
| |
| default_i2c_pins = pinctrl_lookup_state(default_i2c_pinctrl, |
| "default"); |
| if (!IS_ERR(default_i2c_pins)) { |
| default_i2c_pinctrl->state = NULL; |
| status = pinctrl_select_state(default_i2c_pinctrl, default_i2c_pins); |
| if (status) |
| dev_err(i2c->dev, "Can't set default i2c pins!!!\n"); |
| } else { |
| dev_err(i2c->dev, "Can't get default pinstate!!!\n"); |
| } |
| |
| } |
| |
| static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got); |
| |
| /* s3c24xx_get_device_quirks |
| * |
| * Get controller type either from device tree or platform device variant. |
| */ |
| |
| static inline kernel_ulong_t s3c24xx_get_device_quirks(struct platform_device *pdev) |
| { |
| if (pdev->dev.of_node) { |
| const struct of_device_id *match; |
| match = of_match_node(s3c24xx_i2c_match, pdev->dev.of_node); |
| return (kernel_ulong_t)match->data; |
| } |
| |
| return platform_get_device_id(pdev)->driver_data; |
| } |
| |
| /* s3c24xx_i2c_master_complete |
| * |
| * complete the message and wake up the caller, using the given return code, |
| * or zero to mean ok. |
| */ |
| |
| static inline void s3c24xx_i2c_master_complete(struct s3c24xx_i2c *i2c, int ret) |
| { |
| dev_dbg(i2c->dev, "master_complete %d\n", ret); |
| |
| i2c->msg_ptr = 0; |
| i2c->msg = NULL; |
| i2c->msg_idx++; |
| i2c->msg_num = 0; |
| if (ret) |
| i2c->msg_idx = ret; |
| |
| if (!(i2c->quirks & QUIRK_POLL)) |
| wake_up(&i2c->wait); |
| } |
| |
| static inline void s3c24xx_i2c_disable_ack(struct s3c24xx_i2c *i2c) |
| { |
| unsigned long tmp; |
| |
| tmp = readl(i2c->regs + S3C2410_IICCON); |
| writel(tmp & ~S3C2410_IICCON_ACKEN, i2c->regs + S3C2410_IICCON); |
| } |
| |
| static inline void s3c24xx_i2c_enable_ack(struct s3c24xx_i2c *i2c) |
| { |
| unsigned long tmp; |
| |
| tmp = readl(i2c->regs + S3C2410_IICCON); |
| if (i2c->quirks & QUIRK_FIMC_I2C) |
| tmp &= ~S3C2410_IICCON_BUS_RELEASE; |
| writel(tmp | S3C2410_IICCON_ACKEN, i2c->regs + S3C2410_IICCON); |
| } |
| |
| /* irq enable/disable functions */ |
| |
| static inline void s3c24xx_i2c_disable_irq(struct s3c24xx_i2c *i2c) |
| { |
| unsigned long tmp; |
| |
| if (i2c->quirks & QUIRK_FIMC_I2C) { |
| /* disable bus hold interrupt */ |
| tmp = readl(i2c->regs + S3C2410_IICCON); |
| tmp &= ~S3C2410_IICCON_BUSHOLD_IRQEN; |
| writel(tmp, i2c->regs + S3C2410_IICCON); |
| } else { |
| tmp = readl(i2c->regs + S3C2410_IICCON); |
| writel(tmp & ~S3C2410_IICCON_IRQEN, i2c->regs + S3C2410_IICCON); |
| } |
| } |
| |
| static inline void s3c24xx_i2c_enable_irq(struct s3c24xx_i2c *i2c) |
| { |
| unsigned long tmp; |
| |
| if (i2c->quirks & QUIRK_FIMC_I2C) { |
| /* enable bus hold interrupt */ |
| tmp = readl(i2c->regs + S3C2410_IICCON); |
| tmp |= S3C2410_IICCON_BUSHOLD_IRQEN; |
| writel(tmp, i2c->regs + S3C2410_IICCON); |
| } else { |
| tmp = readl(i2c->regs + S3C2410_IICCON); |
| writel(tmp | S3C2410_IICCON_IRQEN, i2c->regs + S3C2410_IICCON); |
| } |
| } |
| |
| static bool is_ack(struct s3c24xx_i2c *i2c) |
| { |
| int tries; |
| |
| for (tries = 50; tries; --tries) { |
| unsigned long tmp = readl(i2c->regs + S3C2410_IICCON); |
| |
| if (!(tmp & S3C2410_IICCON_ACKEN)) { |
| /* |
| * Wait a bit for the bus to stabilize, |
| * delay estimated experimentally. |
| */ |
| usleep_range(100, 200); |
| return true; |
| } |
| if (tmp & S3C2410_IICCON_IRQPEND) { |
| if (!(readl(i2c->regs + S3C2410_IICSTAT) |
| & S3C2410_IICSTAT_LASTBIT)) |
| return true; |
| } |
| udelay(10); |
| } |
| dev_err(i2c->dev, "ack was not received in is_ack\n"); |
| return false; |
| } |
| |
| /* s3c24xx_i2c_message_start |
| * |
| * put the start of a message onto the bus |
| */ |
| |
| static void s3c24xx_i2c_message_start(struct s3c24xx_i2c *i2c, |
| struct i2c_msg *msg) |
| { |
| unsigned int addr = (msg->addr & 0x7f) << 1; |
| unsigned long stat; |
| unsigned long iiccon; |
| |
| stat = 0; |
| stat |= S3C2410_IICSTAT_TXRXEN; |
| |
| if (msg->flags & I2C_M_RD) { |
| stat |= S3C2410_IICSTAT_MASTER_RX; |
| addr |= 1; |
| } else |
| stat |= S3C2410_IICSTAT_MASTER_TX; |
| |
| if (msg->flags & I2C_M_REV_DIR_ADDR) |
| addr ^= 1; |
| |
| /* todo - check for whether ack wanted or not */ |
| iiccon = readl(i2c->regs + S3C2410_IICCON); |
| iiccon |= S3C2410_IICCON_ACKEN; |
| writel(stat, i2c->regs + S3C2410_IICSTAT); |
| |
| dev_dbg(i2c->dev, "START: %08lx to IICSTAT, %02x to DS\n", stat, addr); |
| writeb(addr, i2c->regs + S3C2410_IICDS); |
| |
| /* delay here to ensure the data byte has gotten onto the bus |
| * before the transaction is started */ |
| |
| ndelay(i2c->tx_setup); |
| |
| dev_dbg(i2c->dev, "iiccon, %08lx\n", iiccon); |
| writel(iiccon, i2c->regs + S3C2410_IICCON); |
| |
| stat |= S3C2410_IICSTAT_START; |
| writel(stat, i2c->regs + S3C2410_IICSTAT); |
| } |
| |
| static inline void s3c24xx_i2c_stop(struct s3c24xx_i2c *i2c, int ret) |
| { |
| unsigned long iicstat = readl(i2c->regs + S3C2410_IICSTAT); |
| |
| dev_dbg(i2c->dev, "STOP\n"); |
| |
| /* |
| * The datasheet says that the STOP sequence should be: |
| * 1) I2CSTAT.5 = 0 - Clear BUSY (or 'generate STOP') |
| * 2) I2CCON.4 = 0 - Clear IRQPEND |
| * 3) Wait until the stop condition takes effect. |
| * 4*) I2CSTAT.4 = 0 - Clear TXRXEN |
| * |
| * Where, step "4*" is only for buses with the "HDMIPHY" quirk. |
| * |
| * However, after much experimentation, it appears that: |
| * a) normal buses automatically clear BUSY and transition from |
| * Master->Slave when they complete generating a STOP condition. |
| * Therefore, step (3) can be done in doxfer() by polling I2CCON.4 |
| * after starting the STOP generation here. |
| * b) HDMIPHY bus does neither, so there is no way to do step 3. |
| * There is no indication when this bus has finished generating |
| * STOP. |
| * |
| * In fact, we have found that as soon as the IRQPEND bit is cleared in |
| * step 2, the HDMIPHY bus generates the STOP condition, and then |
| * immediately starts transferring another data byte, even though the |
| * bus is supposedly stopped. This is presumably because the bus is |
| * still in "Master" mode, and its BUSY bit is still set. |
| * |
| * To avoid these extra post-STOP transactions on HDMI phy devices, we |
| * just disable Serial Output on the bus (I2CSTAT.4 = 0) directly, |
| * instead of first generating a proper STOP condition. This should |
| * float SDA & SCK terminating the transfer. Subsequent transfers |
| * start with a proper START condition, and proceed normally. |
| * |
| * The HDMIPHY bus is an internal bus that always has exactly two |
| * devices, the host as Master and the HDMIPHY device as the slave. |
| * Skipping the STOP condition has been tested on this bus and works. |
| */ |
| if (i2c->quirks & QUIRK_HDMIPHY) { |
| /* Stop driving the I2C pins */ |
| iicstat &= ~S3C2410_IICSTAT_TXRXEN; |
| } else { |
| /* stop the transfer */ |
| iicstat &= ~S3C2410_IICSTAT_START; |
| } |
| writel(iicstat, i2c->regs + S3C2410_IICSTAT); |
| |
| i2c->state = STATE_STOP; |
| |
| s3c24xx_i2c_master_complete(i2c, ret); |
| s3c24xx_i2c_disable_irq(i2c); |
| } |
| |
| /* helper functions to determine the current state in the set of |
| * messages we are sending */ |
| |
| /* is_lastmsg() |
| * |
| * returns TRUE if the current message is the last in the set |
| */ |
| |
| static inline int is_lastmsg(struct s3c24xx_i2c *i2c) |
| { |
| return i2c->msg_idx >= (i2c->msg_num - 1); |
| } |
| |
| /* is_msglast |
| * |
| * returns TRUE if we this is the last byte in the current message |
| */ |
| |
| static inline int is_msglast(struct s3c24xx_i2c *i2c) |
| { |
| /* msg->len is always 1 for the first byte of smbus block read. |
| * Actual length will be read from slave. More bytes will be |
| * read according to the length then. */ |
| if (i2c->msg->flags & I2C_M_RECV_LEN && i2c->msg->len == 1) |
| return 0; |
| |
| return i2c->msg_ptr == i2c->msg->len-1; |
| } |
| |
| /* is_msgend |
| * |
| * returns TRUE if we reached the end of the current message |
| */ |
| |
| static inline int is_msgend(struct s3c24xx_i2c *i2c) |
| { |
| return i2c->msg_ptr >= i2c->msg->len; |
| } |
| |
| /* i2c_s3c_irq_nextbyte |
| * |
| * process an interrupt and work out what to do |
| */ |
| |
| static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat) |
| { |
| unsigned long tmp; |
| unsigned char byte; |
| int ret = 0; |
| |
| switch (i2c->state) { |
| |
| case STATE_IDLE: |
| dev_err(i2c->dev, "%s: called in STATE_IDLE\n", __func__); |
| goto out; |
| |
| case STATE_STOP: |
| dev_err(i2c->dev, "%s: called in STATE_STOP\n", __func__); |
| s3c24xx_i2c_disable_irq(i2c); |
| goto out_ack; |
| |
| case STATE_START: |
| /* last thing we did was send a start condition on the |
| * bus, or started a new i2c message |
| */ |
| |
| if (iicstat & S3C2410_IICSTAT_LASTBIT && |
| !(i2c->msg->flags & I2C_M_IGNORE_NAK)) { |
| /* ack was not received... */ |
| |
| dev_err(i2c->dev, "ack was not received irq_nextbyte\n"); |
| s3c24xx_i2c_stop(i2c, -ENXIO); |
| goto out_ack; |
| } |
| |
| if (i2c->msg->flags & I2C_M_RD) |
| i2c->state = STATE_READ; |
| else |
| i2c->state = STATE_WRITE; |
| |
| /* terminate the transfer if there is nothing to do |
| * as this is used by the i2c probe to find devices. */ |
| |
| if (is_lastmsg(i2c) && i2c->msg->len == 0) { |
| s3c24xx_i2c_stop(i2c, 0); |
| goto out_ack; |
| } |
| |
| if (i2c->state == STATE_READ) |
| goto prepare_read; |
| |
| /* fall through to the write state, as we will need to |
| * send a byte as well */ |
| |
| case STATE_WRITE: |
| /* we are writing data to the device... check for the |
| * end of the message, and if so, work out what to do |
| */ |
| |
| if (!(i2c->msg->flags & I2C_M_IGNORE_NAK)) { |
| if (iicstat & S3C2410_IICSTAT_LASTBIT) { |
| dev_dbg(i2c->dev, "WRITE: No Ack\n"); |
| |
| s3c24xx_i2c_stop(i2c, -ECONNREFUSED); |
| goto out_ack; |
| } |
| } |
| |
| retry_write: |
| |
| if (!is_msgend(i2c)) { |
| byte = i2c->msg->buf[i2c->msg_ptr++]; |
| writeb(byte, i2c->regs + S3C2410_IICDS); |
| |
| /* delay after writing the byte to allow the |
| * data setup time on the bus, as writing the |
| * data to the register causes the first bit |
| * to appear on SDA, and SCL will change as |
| * soon as the interrupt is acknowledged */ |
| |
| ndelay(i2c->tx_setup); |
| |
| } else if (!is_lastmsg(i2c)) { |
| /* we need to go to the next i2c message */ |
| |
| dev_dbg(i2c->dev, "WRITE: Next Message\n"); |
| |
| i2c->msg_ptr = 0; |
| i2c->msg_idx++; |
| i2c->msg++; |
| |
| /* check to see if we need to do another message */ |
| if (i2c->msg->flags & I2C_M_NOSTART) { |
| |
| if (i2c->msg->flags & I2C_M_RD) { |
| /* cannot do this, the controller |
| * forces us to send a new START |
| * when we change direction */ |
| |
| dev_dbg(i2c->dev, |
| "missing START before write->read\n"); |
| s3c24xx_i2c_stop(i2c, -EINVAL); |
| break; |
| } |
| |
| goto retry_write; |
| } else { |
| /* send the new start */ |
| s3c24xx_i2c_message_start(i2c, i2c->msg); |
| i2c->state = STATE_START; |
| } |
| |
| } else { |
| /* send stop */ |
| |
| s3c24xx_i2c_stop(i2c, 0); |
| } |
| break; |
| |
| case STATE_READ: |
| /* we have a byte of data in the data register, do |
| * something with it, and then work out whether we are |
| * going to do any more read/write |
| */ |
| |
| byte = readb(i2c->regs + S3C2410_IICDS); |
| i2c->msg->buf[i2c->msg_ptr++] = byte; |
| |
| /* Add actual length to read for smbus block read */ |
| if (i2c->msg->flags & I2C_M_RECV_LEN && i2c->msg->len == 1) |
| i2c->msg->len += byte; |
| prepare_read: |
| if (is_msglast(i2c)) { |
| /* last byte of buffer */ |
| |
| if (is_lastmsg(i2c)) |
| s3c24xx_i2c_disable_ack(i2c); |
| |
| } else if (is_msgend(i2c)) { |
| /* ok, we've read the entire buffer, see if there |
| * is anything else we need to do */ |
| |
| if (is_lastmsg(i2c)) { |
| /* last message, send stop and complete */ |
| dev_dbg(i2c->dev, "READ: Send Stop\n"); |
| |
| s3c24xx_i2c_stop(i2c, 0); |
| } else { |
| /* go to the next transfer */ |
| dev_dbg(i2c->dev, "READ: Next Transfer\n"); |
| |
| i2c->msg_ptr = 0; |
| i2c->msg_idx++; |
| i2c->msg++; |
| } |
| } |
| |
| break; |
| } |
| |
| /* acknowlegde the IRQ and get back on with the work */ |
| |
| out_ack: |
| if (i2c->quirks & QUIRK_FIMC_I2C) { |
| /* clear bus hold status flag */ |
| tmp = readl(i2c->regs + S3C2440_IICINT); |
| tmp |= S3C2440_IICINT_BUSHOLD_CLEAR; |
| writel(tmp, i2c->regs + S3C2440_IICINT); |
| |
| /* release the i2c bus */ |
| tmp = readl(i2c->regs + S3C2410_IICCON); |
| tmp |= S3C2410_IICCON_IRQPEND; |
| writel(tmp, i2c->regs + S3C2410_IICCON); |
| } else { |
| tmp = readl(i2c->regs + S3C2410_IICCON); |
| tmp &= ~S3C2410_IICCON_IRQPEND; |
| writel(tmp, i2c->regs + S3C2410_IICCON); |
| } |
| out: |
| return ret; |
| } |
| |
| /* s3c24xx_i2c_irq |
| * |
| * top level IRQ servicing routine |
| */ |
| |
| static irqreturn_t s3c24xx_i2c_irq(int irqno, void *dev_id) |
| { |
| struct s3c24xx_i2c *i2c = dev_id; |
| unsigned long status; |
| unsigned long tmp; |
| |
| status = readl(i2c->regs + S3C2410_IICSTAT); |
| |
| if (status & S3C2410_IICSTAT_ARBITR) { |
| /* deal with arbitration loss */ |
| dev_err(i2c->dev, "deal with arbitration loss\n"); |
| if (i2c->fix_doxfer_return) { |
| i2c->msg_idx = -ECONNREFUSED; |
| goto out; |
| } |
| } |
| |
| if (i2c->state == STATE_IDLE) { |
| dev_dbg(i2c->dev, "IRQ: error i2c->state == IDLE\n"); |
| if (i2c->quirks & QUIRK_FIMC_I2C) { |
| /* clear bus hold status flag */ |
| tmp = readl(i2c->regs + S3C2440_IICINT); |
| tmp |= S3C2440_IICINT_BUSHOLD_CLEAR; |
| writel(tmp, i2c->regs + S3C2440_IICINT); |
| |
| /* release the i2c bus */ |
| tmp = readl(i2c->regs + S3C2410_IICCON); |
| tmp |= S3C2410_IICCON_IRQPEND; |
| writel(tmp, i2c->regs + S3C2410_IICCON); |
| } else { |
| tmp = readl(i2c->regs + S3C2410_IICCON); |
| tmp &= ~S3C2410_IICCON_IRQPEND; |
| writel(tmp, i2c->regs + S3C2410_IICCON); |
| } |
| goto out; |
| } |
| |
| /* pretty much this leaves us with the fact that we've |
| * transmitted or received whatever byte we last sent */ |
| |
| i2c_s3c_irq_nextbyte(i2c, status); |
| |
| out: |
| return IRQ_HANDLED; |
| } |
| |
| /* |
| * Disable the bus so that we won't get any interrupts from now on, or try |
| * to drive any lines. This is the default state when we don't have |
| * anything to send/receive. |
| * |
| * If there is an event on the bus, or we have a pre-existing event at |
| * kernel boot time, we may not notice the event and the I2C controller |
| * will lock the bus with the I2C clock line low indefinitely. |
| */ |
| static inline void s3c24xx_i2c_disable_bus(struct s3c24xx_i2c *i2c) |
| { |
| unsigned long tmp; |
| |
| /* Stop driving the I2C pins */ |
| tmp = readl(i2c->regs + S3C2410_IICSTAT); |
| tmp &= ~S3C2410_IICSTAT_TXRXEN; |
| writel(tmp, i2c->regs + S3C2410_IICSTAT); |
| |
| /* We don't expect any interrupts now, and don't want send acks */ |
| tmp = readl(i2c->regs + S3C2410_IICCON); |
| tmp &= ~(S3C2410_IICCON_IRQEN | S3C2410_IICCON_IRQPEND | |
| S3C2410_IICCON_ACKEN); |
| writel(tmp, i2c->regs + S3C2410_IICCON); |
| } |
| |
| |
| /* s3c24xx_i2c_set_master |
| * |
| * get the i2c bus for a master transaction |
| */ |
| |
| static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c) |
| { |
| unsigned long iicstat; |
| int timeout = 400; |
| |
| while (timeout-- > 0) { |
| iicstat = readl(i2c->regs + S3C2410_IICSTAT); |
| |
| if (!(iicstat & S3C2410_IICSTAT_BUSBUSY)) |
| return 0; |
| |
| msleep(1); |
| } |
| |
| return -ETIMEDOUT; |
| } |
| |
| /* s3c24xx_i2c_wait_idle |
| * |
| * wait for the i2c bus to become idle. |
| */ |
| |
| static void s3c24xx_i2c_wait_idle(struct s3c24xx_i2c *i2c) |
| { |
| unsigned long iicstat; |
| ktime_t start, now; |
| unsigned long delay; |
| int spins; |
| |
| /* ensure the stop has been through the bus */ |
| |
| dev_dbg(i2c->dev, "waiting for bus idle\n"); |
| |
| start = now = ktime_get(); |
| |
| /* |
| * Most of the time, the bus is already idle within a few usec of the |
| * end of a transaction. However, really slow i2c devices can stretch |
| * the clock, delaying STOP generation. |
| * |
| * On slower SoCs this typically happens within a very small number of |
| * instructions so busy wait briefly to avoid scheduling overhead. |
| */ |
| spins = 3; |
| iicstat = readl(i2c->regs + S3C2410_IICSTAT); |
| while ((iicstat & S3C2410_IICSTAT_START) && --spins) { |
| cpu_relax(); |
| iicstat = readl(i2c->regs + S3C2410_IICSTAT); |
| } |
| |
| /* |
| * If we do get an appreciable delay as a compromise between idle |
| * detection latency for the normal, fast case, and system load in the |
| * slow device case, use an exponential back off in the polling loop, |
| * up to 1/10th of the total timeout, then continue to poll at a |
| * constant rate up to the timeout. |
| */ |
| delay = 1; |
| while ((iicstat & S3C2410_IICSTAT_START) && |
| ktime_us_delta(now, start) < S3C2410_IDLE_TIMEOUT) { |
| usleep_range(delay, 2 * delay); |
| if (delay < S3C2410_IDLE_TIMEOUT / 10) |
| delay <<= 1; |
| now = ktime_get(); |
| iicstat = readl(i2c->regs + S3C2410_IICSTAT); |
| } |
| |
| if (iicstat & S3C2410_IICSTAT_START) { |
| dev_warn(i2c->dev, "timeout waiting for bus idle\n" |
| "I2C Stat Reg dump:\n" |
| "IIC STAT = 0x%08x\n" |
| , readl(i2c->regs + S3C2410_IICSTAT)); |
| if (i2c->state != STATE_STOP) |
| s3c24xx_i2c_stop(i2c, -ENXIO); |
| } |
| } |
| |
| /* s3c24xx_i2c_doxfer |
| * |
| * this starts an i2c transfer |
| */ |
| |
| static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, |
| struct i2c_msg *msgs, int num) |
| { |
| unsigned long timeout = 0; |
| int ret; |
| |
| if (i2c->suspended) |
| return -EIO; |
| |
| ret = s3c24xx_i2c_set_master(i2c); |
| if (ret != 0) { |
| dev_err(i2c->dev, "cannot get bus (error %d)\n", ret); |
| i2c->need_hw_init = S3C2410_NEED_FULL_INIT; |
| ret = -EAGAIN; |
| goto out; |
| } |
| |
| i2c->msg = msgs; |
| i2c->msg_num = num; |
| i2c->msg_ptr = 0; |
| i2c->msg_idx = 0; |
| i2c->state = STATE_START; |
| |
| s3c24xx_i2c_enable_irq(i2c); |
| s3c24xx_i2c_message_start(i2c, msgs); |
| |
| if (i2c->quirks & QUIRK_POLL) { |
| while ((i2c->msg_num != 0) && is_ack(i2c)) { |
| unsigned long stat = readl(i2c->regs + S3C2410_IICSTAT); |
| |
| i2c_s3c_irq_nextbyte(i2c, stat); |
| |
| stat = readl(i2c->regs + S3C2410_IICSTAT); |
| if (stat & S3C2410_IICSTAT_ARBITR) |
| dev_err(i2c->dev, "deal with arbitration loss\n"); |
| } |
| } else { |
| timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5); |
| } |
| |
| ret = i2c->msg_idx; |
| |
| /* having these next two as dev_err() makes life very |
| * noisy when doing an i2cdetect */ |
| |
| if (timeout == 0) { |
| dev_err(i2c->dev, "timeout\n"); |
| dev_err(i2c->dev, "incomplete xfer (%d)\n" |
| "I2C Stat Reg dump:\n" |
| "IIC STAT = 0x%08x\n" |
| "IIC CON = 0x%08x\n" |
| , ret |
| , readl(i2c->regs + S3C2410_IICSTAT) |
| , readl(i2c->regs + S3C2410_IICCON)); |
| if (i2c->fix_doxfer_return && (ret >= 0)) { |
| ret = -ETIMEDOUT; |
| } |
| recover_i2c_gpio(i2c); |
| } |
| else if (ret != num) { |
| dev_err(i2c->dev, "sent lengh(%d) don't match requested length(%d)\n", ret, num); |
| dev_err(i2c->dev, "incomplete xfer (%d)\n" |
| "I2C Stat Reg dump:\n" |
| "IIC STAT = 0x%08x\n" |
| "IIC CON = 0x%08x\n" |
| , ret |
| , readl(i2c->regs + S3C2410_IICSTAT) |
| , readl(i2c->regs + S3C2410_IICCON)); |
| if (i2c->fix_doxfer_return) { |
| recover_i2c_gpio(i2c); |
| if (ret >= 0) |
| ret = -EIO; |
| } |
| } |
| |
| /* For QUIRK_HDMIPHY, bus is already disabled */ |
| if (i2c->quirks & QUIRK_HDMIPHY) |
| goto out; |
| |
| s3c24xx_i2c_wait_idle(i2c); |
| |
| s3c24xx_i2c_disable_bus(i2c); |
| |
| out: |
| i2c->state = STATE_IDLE; |
| |
| return ret; |
| } |
| |
| /* s3c24xx_i2c_xfer |
| * |
| * first port of call from the i2c bus code when an message needs |
| * transferring across the i2c bus. |
| */ |
| static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c); |
| |
| static int s3c24xx_i2c_xfer(struct i2c_adapter *adap, |
| struct i2c_msg *msgs, int num) |
| { |
| struct s3c24xx_i2c *i2c = (struct s3c24xx_i2c *)adap->algo_data; |
| int retry; |
| int ret; |
| |
| #ifdef CONFIG_ARCH_EXYNOS_PM |
| exynos_update_ip_idle_status(i2c->idle_ip_index, 0); |
| #endif |
| ret = clk_enable(i2c->clk); |
| if (ret) |
| return ret; |
| |
| if (i2c->reset_before_trans) |
| i2c->need_hw_init = S3C2410_NEED_FULL_INIT; |
| |
| for (retry = 0; retry < adap->retries; retry++) { |
| |
| if (i2c->need_hw_init & S3C2410_NEED_FULL_INIT) |
| s3c24xx_i2c_init(i2c); |
| |
| ret = s3c24xx_i2c_doxfer(i2c, msgs, num); |
| |
| if (ret != -EAGAIN) { |
| clk_disable(i2c->clk); |
| #ifdef CONFIG_ARCH_EXYNOS_PM |
| exynos_update_ip_idle_status(i2c->idle_ip_index, 1); |
| #endif |
| return ret; |
| } |
| |
| dev_dbg(i2c->dev, "Retrying transmission (%d)\n", retry); |
| |
| udelay(100); |
| } |
| |
| clk_disable(i2c->clk); |
| #ifdef CONFIG_ARCH_EXYNOS_PM |
| exynos_update_ip_idle_status(i2c->idle_ip_index, 1); |
| #endif |
| return -EREMOTEIO; |
| } |
| |
| /* declare our i2c functionality */ |
| static u32 s3c24xx_i2c_func(struct i2c_adapter *adap) |
| { |
| return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_NOSTART | |
| I2C_FUNC_PROTOCOL_MANGLING; |
| } |
| |
| /* i2c bus registration info */ |
| |
| static const struct i2c_algorithm s3c24xx_i2c_algorithm = { |
| .master_xfer = s3c24xx_i2c_xfer, |
| .functionality = s3c24xx_i2c_func, |
| }; |
| |
| /* s3c24xx_i2c_calcdivisor |
| * |
| * return the divisor settings for a given frequency |
| */ |
| |
| static int s3c24xx_i2c_calcdivisor(struct s3c24xx_i2c *i2c, |
| unsigned long clkin, unsigned int wanted, |
| unsigned int *div1, unsigned int *divs) |
| { |
| unsigned int calc_divs = clkin / wanted; |
| unsigned int calc_div1; |
| unsigned int clk_prescaler; |
| |
| if (i2c->quirks & QUIRK_FIMC_I2C) { |
| /* Input NCLK is used directly in i2c */ |
| writel(0, i2c->regs + S3C2440_IICNCLK_DIV2); |
| writeb(1, i2c->regs + S3C2440_CLK_BYPASS); |
| clk_prescaler = 32; |
| } else |
| clk_prescaler = 16; |
| |
| if (calc_divs > (16*16)) |
| calc_div1 = 512; |
| else |
| calc_div1 = clk_prescaler; |
| |
| calc_divs += calc_div1-1; |
| calc_divs /= calc_div1; |
| |
| if (calc_divs == 0) |
| calc_divs = 1; |
| if (calc_divs > (clk_prescaler + 1)) |
| calc_divs = clk_prescaler + 1; |
| |
| *divs = calc_divs; |
| *div1 = calc_div1; |
| |
| return clkin / (calc_divs * calc_div1); |
| } |
| |
| /* s3c24xx_i2c_clockrate |
| * |
| * work out a divisor for the user requested frequency setting, |
| * either by the requested frequency, or scanning the acceptable |
| * range of frequencies until something is found |
| */ |
| |
| static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got) |
| { |
| struct s3c2410_platform_i2c *pdata = i2c->pdata; |
| unsigned long clkin; |
| unsigned int divs, div1; |
| unsigned long target_frequency; |
| u32 iiccon; |
| int freq; |
| |
| if (i2c->quirks & QUIRK_FIMC_I2C) |
| clkin = 24000000;/* NCLK is fixed 24Mhz */ |
| else |
| clkin = clk_get_rate(i2c->rate_clk); |
| |
| i2c->clkrate = clkin; |
| clkin /= 1000; /* clkin now in KHz */ |
| |
| dev_dbg(i2c->dev, "pdata desired frequency %lu\n", pdata->frequency); |
| |
| target_frequency = pdata->frequency ? pdata->frequency : 100000; |
| |
| target_frequency /= 1000; /* Target frequency now in KHz */ |
| |
| freq = s3c24xx_i2c_calcdivisor(i2c, clkin, |
| target_frequency, &div1, &divs); |
| |
| if (freq > target_frequency) { |
| dev_err(i2c->dev, |
| "Unable to achieve desired frequency %luKHz." \ |
| " Lowest achievable %dKHz\n", target_frequency, freq); |
| return -EINVAL; |
| } |
| |
| *got = freq; |
| |
| iiccon = readl(i2c->regs + S3C2410_IICCON); |
| iiccon &= ~(S3C2410_IICCON_SCALEMASK | S3C2410_IICCON_TXDIV_512); |
| iiccon |= (divs-1); |
| |
| if (div1 == 512) |
| iiccon |= S3C2410_IICCON_TXDIV_512; |
| |
| writel(iiccon, i2c->regs + S3C2410_IICCON); |
| |
| if (i2c->quirks & QUIRK_S3C2440) { |
| unsigned long sda_delay; |
| |
| if (pdata->sda_delay) { |
| sda_delay = clkin * pdata->sda_delay; |
| sda_delay = DIV_ROUND_UP(sda_delay, 1000000); |
| sda_delay = DIV_ROUND_UP(sda_delay, 5); |
| if (sda_delay > 3) |
| sda_delay = 3; |
| sda_delay |= S3C2410_IICLC_FILTER_ON; |
| } else |
| sda_delay = 0; |
| |
| if (i2c->filter_on) |
| sda_delay |= S3C2410_IICLC_FILTER_ON; |
| |
| dev_dbg(i2c->dev, "IICLC=%08lx\n", sda_delay); |
| writel(sda_delay, i2c->regs + S3C2440_IICLC); |
| } |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_OF |
| static int s3c24xx_i2c_parse_dt_gpio(struct s3c24xx_i2c *i2c) |
| { |
| int idx, gpio, ret; |
| |
| if (i2c->quirks & QUIRK_NO_GPIO) |
| return 0; |
| |
| 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, "i2c-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 s3c24xx_i2c_dt_gpio_free(struct s3c24xx_i2c *i2c) |
| { |
| unsigned int idx; |
| |
| if (i2c->quirks & QUIRK_NO_GPIO) |
| return; |
| |
| for (idx = 0; idx < 2; idx++) |
| gpio_free(i2c->gpios[idx]); |
| } |
| #else |
| static int s3c24xx_i2c_parse_dt_gpio(struct s3c24xx_i2c *i2c) |
| { |
| return 0; |
| } |
| |
| static void s3c24xx_i2c_dt_gpio_free(struct s3c24xx_i2c *i2c) |
| { |
| } |
| #endif |
| |
| /* s3c24xx_i2c_init |
| * |
| * initialise the controller, set the IO lines and frequency |
| */ |
| |
| static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c) |
| { |
| struct s3c2410_platform_i2c *pdata; |
| unsigned long iicstat = readl(i2c->regs + S3C2410_IICSTAT); |
| unsigned int freq; |
| |
| /* get the plafrom data */ |
| |
| pdata = i2c->pdata; |
| |
| if (i2c->need_hw_init & S3C2410_NEED_BUS_INIT) { |
| /* reset i2c bus to recover from "cannot get bus" */ |
| iicstat &= ~S3C2410_IICSTAT_TXRXEN; |
| writel(iicstat, i2c->regs + S3C2410_IICSTAT); |
| } |
| |
| /* write slave address */ |
| writeb(pdata->slave_addr, i2c->regs + S3C2410_IICADD); |
| |
| dev_dbg(i2c->dev, "slave address 0x%02x\n", pdata->slave_addr); |
| |
| writel(0, i2c->regs + S3C2410_IICCON); |
| writel(0, i2c->regs + S3C2410_IICSTAT); |
| |
| /* we need to work out the divisors for the clock... */ |
| |
| if (s3c24xx_i2c_clockrate(i2c, &freq) != 0) { |
| dev_err(i2c->dev, "cannot meet bus frequency required\n"); |
| return -EINVAL; |
| } |
| |
| /* todo - check that the i2c lines aren't being dragged anywhere */ |
| |
| dev_dbg(i2c->dev, "bus frequency set to %d KHz\n", freq); |
| dev_dbg(i2c->dev, "S3C2410_IICCON=0x%02x\n", |
| readl(i2c->regs + S3C2410_IICCON)); |
| |
| i2c->need_hw_init = 0; |
| return 0; |
| } |
| |
| #ifdef CONFIG_OF |
| /* s3c24xx_i2c_parse_dt |
| * |
| * Parse the device tree node and retreive the platform data. |
| */ |
| |
| static void |
| s3c24xx_i2c_parse_dt(struct device_node *np, struct s3c24xx_i2c *i2c) |
| { |
| struct s3c2410_platform_i2c *pdata = i2c->pdata; |
| |
| if (!np) |
| return; |
| |
| pdata->bus_num = -1; /* i2c bus number is dynamically assigned */ |
| of_property_read_u32(np, "samsung,i2c-sda-delay", &pdata->sda_delay); |
| of_property_read_u32(np, "samsung,i2c-slave-addr", &pdata->slave_addr); |
| of_property_read_u32(np, "samsung,i2c-max-bus-freq", |
| (u32 *)&pdata->frequency); |
| } |
| #else |
| static void |
| s3c24xx_i2c_parse_dt(struct device_node *np, struct s3c24xx_i2c *i2c) |
| { |
| return; |
| } |
| #endif |
| |
| #ifdef CONFIG_CPU_IDLE |
| static int s3c24xx_i2c_notifier(struct notifier_block *self, |
| unsigned long cmd, void *v) |
| { |
| struct s3c24xx_i2c *i2c; |
| |
| switch (cmd) { |
| case LPA_EXIT: |
| list_for_each_entry(i2c, &drvdata_list, node) |
| i2c->need_hw_init = S3C2410_NEED_REG_INIT; |
| break; |
| } |
| |
| return NOTIFY_OK; |
| } |
| |
| static struct notifier_block s3c24xx_i2c_notifier_block = { |
| .notifier_call = s3c24xx_i2c_notifier, |
| }; |
| #endif /* CONFIG_CPU_IDLE */ |
| |
| /* s3c24xx_i2c_probe |
| * |
| * called by the bus driver when a suitable device is found |
| */ |
| |
| static int s3c24xx_i2c_probe(struct platform_device *pdev) |
| { |
| struct s3c24xx_i2c *i2c; |
| struct s3c2410_platform_i2c *pdata = NULL; |
| struct resource *res; |
| int ret; |
| |
| if (!pdev->dev.of_node) { |
| pdata = dev_get_platdata(&pdev->dev); |
| if (!pdata) { |
| dev_err(&pdev->dev, "no platform data\n"); |
| return -EINVAL; |
| } |
| } |
| |
| i2c = devm_kzalloc(&pdev->dev, sizeof(struct s3c24xx_i2c), GFP_KERNEL); |
| if (!i2c) |
| return -ENOMEM; |
| |
| i2c->pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); |
| if (!i2c->pdata) |
| return -ENOMEM; |
| |
| i2c->quirks = s3c24xx_get_device_quirks(pdev); |
| if (pdata) |
| memcpy(i2c->pdata, pdata, sizeof(*pdata)); |
| else |
| s3c24xx_i2c_parse_dt(pdev->dev.of_node, i2c); |
| |
| if (of_get_property(pdev->dev.of_node, "samsung,reset-before-trans", NULL)) |
| i2c->reset_before_trans = 1; |
| else |
| i2c->reset_before_trans = 0; |
| |
| if (of_get_property(pdev->dev.of_node, "samsung,fix-doxfer-return", NULL)) |
| i2c->fix_doxfer_return = 1; |
| else |
| i2c->fix_doxfer_return = 0; |
| |
| if (of_get_property(pdev->dev.of_node, "samsung,glitch-filter", NULL)) |
| i2c->filter_on = 1; |
| else |
| i2c->filter_on = 0; |
| |
| strlcpy(i2c->adap.name, "s3c2410-i2c", sizeof(i2c->adap.name)); |
| i2c->adap.owner = THIS_MODULE; |
| i2c->adap.algo = &s3c24xx_i2c_algorithm; |
| i2c->adap.retries = 2; |
| i2c->adap.class = I2C_CLASS_DEPRECATED; |
| i2c->tx_setup = 50; |
| |
| #ifdef CONFIG_ARCH_EXYNOS_PM |
| i2c->idle_ip_index = exynos_get_idle_ip_index(dev_name(&pdev->dev)); |
| #endif |
| |
| init_waitqueue_head(&i2c->wait); |
| |
| /* find the clock and enable it */ |
| |
| i2c->dev = &pdev->dev; |
| i2c->rate_clk = devm_clk_get(&pdev->dev, "rate_i2c"); |
| if (IS_ERR(i2c->rate_clk)) { |
| dev_err(&pdev->dev, "cannot get rate clock\n"); |
| return -ENOENT; |
| } |
| |
| i2c->clk = devm_clk_get(&pdev->dev, "gate_i2c"); |
| if (IS_ERR(i2c->clk)) { |
| dev_err(&pdev->dev, "cannot get clock\n"); |
| return -ENOENT; |
| } |
| |
| dev_dbg(&pdev->dev, "clock source %p\n", i2c->clk); |
| |
| ret = clk_prepare(i2c->clk); |
| if (ret) { |
| dev_err(&pdev->dev, "I2C clock prepare failed\n"); |
| return ret; |
| } |
| |
| /* map the registers */ |
| |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| i2c->regs = devm_ioremap_resource(&pdev->dev, res); |
| |
| if (IS_ERR(i2c->regs)) |
| return PTR_ERR(i2c->regs); |
| |
| dev_dbg(&pdev->dev, "registers %p (%p)\n", |
| i2c->regs, res); |
| |
| /* setup info block for the i2c core */ |
| |
| i2c->adap.algo_data = i2c; |
| i2c->adap.dev.parent = &pdev->dev; |
| |
| i2c->pctrl = devm_pinctrl_get_select_default(i2c->dev); |
| |
| /* inititalise the i2c gpio lines */ |
| |
| if (i2c->pdata->cfg_gpio) { |
| i2c->pdata->cfg_gpio(to_platform_device(i2c->dev)); |
| } else if (IS_ERR(i2c->pctrl) && s3c24xx_i2c_parse_dt_gpio(i2c)) { |
| return -EINVAL; |
| } |
| |
| i2c->need_hw_init = S3C2410_NEED_REG_INIT; |
| |
| /* find the IRQ for this unit (note, this relies on the init call to |
| * ensure no current IRQs pending |
| */ |
| |
| if (!(i2c->quirks & QUIRK_POLL)) { |
| i2c->irq = ret = platform_get_irq(pdev, 0); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "cannot find IRQ\n"); |
| clk_unprepare(i2c->clk); |
| return ret; |
| } |
| |
| ret = devm_request_irq(&pdev->dev, i2c->irq, s3c24xx_i2c_irq, 0, |
| dev_name(&pdev->dev), i2c); |
| |
| if (ret != 0) { |
| dev_err(&pdev->dev, "cannot claim IRQ %d\n", i2c->irq); |
| clk_unprepare(i2c->clk); |
| return ret; |
| } |
| } |
| |
| /* Note, previous versions of the driver used i2c_add_adapter() |
| * to add the bus at any number. We now pass the bus number via |
| * the platform data, so if unset it will now default to always |
| * being bus 0. |
| */ |
| |
| i2c->adap.nr = i2c->pdata->bus_num; |
| i2c->adap.dev.of_node = pdev->dev.of_node; |
| |
| platform_set_drvdata(pdev, i2c); |
| |
| pm_runtime_enable(&pdev->dev); |
| |
| ret = i2c_add_numbered_adapter(&i2c->adap); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "failed to add bus to i2c core\n"); |
| pm_runtime_disable(&pdev->dev); |
| clk_unprepare(i2c->clk); |
| return ret; |
| } |
| |
| |
| #ifdef CONFIG_CPU_IDLE |
| list_add_tail(&i2c->node, &drvdata_list); |
| #endif |
| |
| dev_info(&pdev->dev, "%s: S3C I2C adapter\n", dev_name(&i2c->adap.dev)); |
| return 0; |
| } |
| |
| /* s3c24xx_i2c_remove |
| * |
| * called when device is removed from the bus |
| */ |
| |
| static int s3c24xx_i2c_remove(struct platform_device *pdev) |
| { |
| struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev); |
| |
| clk_unprepare(i2c->clk); |
| |
| pm_runtime_disable(&pdev->dev); |
| |
| i2c_del_adapter(&i2c->adap); |
| |
| if (pdev->dev.of_node && IS_ERR(i2c->pctrl)) |
| s3c24xx_i2c_dt_gpio_free(i2c); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| static int s3c24xx_i2c_suspend_noirq(struct device *dev) |
| { |
| struct s3c24xx_i2c *i2c = dev_get_drvdata(dev); |
| |
| dev_err(i2c->dev, "Device %s\n", __func__); |
| |
| i2c->suspended = 1; |
| |
| return 0; |
| } |
| |
| static int s3c24xx_i2c_resume_noirq(struct device *dev) |
| { |
| struct platform_device *pdev = to_platform_device(dev); |
| struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev); |
| |
| i2c->suspended = 0; |
| i2c->need_hw_init = S3C2410_NEED_REG_INIT; |
| |
| return 0; |
| } |
| #endif |
| |
| #ifdef CONFIG_PM |
| static int s3c24xx_i2c_runtime_resume(struct device *dev) |
| { |
| struct platform_device *pdev = to_platform_device(dev); |
| struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev); |
| |
| dev_err(i2c->dev, "Device %s\n", __func__); |
| |
| if (i2c->quirks & QUIRK_FIMC_I2C) |
| i2c->need_hw_init = S3C2410_NEED_REG_INIT; |
| |
| return 0; |
| } |
| #endif |
| |
| #ifdef CONFIG_SAMSUNG_TUI |
| int stui_i2c_lock(struct i2c_adapter *adap) |
| { |
| int ret = 0; |
| struct s3c24xx_i2c *stui_i2c; |
| |
| if (!adap) { |
| pr_err("cannot get adapter\n"); |
| return -1; |
| } |
| |
| i2c_lock_adapter(adap); |
| stui_i2c = (struct s3c24xx_i2c *)adap->algo_data; |
| |
| ret = clk_enable(stui_i2c->clk); |
| if (ret) |
| goto out_err; |
| |
| #ifdef CONFIG_ARCH_EXYNOS_PM |
| exynos_update_ip_idle_status(stui_i2c->idle_ip_index, 0); |
| #endif |
| |
| return 0; |
| |
| out_err: |
| i2c_unlock_adapter(adap); |
| return ret; |
| } |
| |
| int stui_i2c_unlock(struct i2c_adapter *adap) |
| { |
| struct s3c24xx_i2c *stui_i2c; |
| |
| if (!adap) { |
| pr_err("cannot get adapter\n"); |
| return -1; |
| } |
| |
| stui_i2c = (struct s3c24xx_i2c *)adap->algo_data; |
| |
| clk_disable(stui_i2c->clk); |
| |
| #ifdef CONFIG_ARCH_EXYNOS_PM |
| exynos_update_ip_idle_status(stui_i2c->idle_ip_index, 1); |
| #endif |
| |
| i2c_unlock_adapter(adap); |
| |
| return 0; |
| } |
| #endif /* CONFIG_SAMSUNG_TUI */ |
| |
| #ifdef CONFIG_PM |
| static const struct dev_pm_ops s3c24xx_i2c_dev_pm_ops = { |
| SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(s3c24xx_i2c_suspend_noirq, |
| s3c24xx_i2c_resume_noirq) |
| .runtime_resume = s3c24xx_i2c_runtime_resume, |
| }; |
| |
| #define S3C24XX_DEV_PM_OPS (&s3c24xx_i2c_dev_pm_ops) |
| #else |
| #define S3C24XX_DEV_PM_OPS NULL |
| #endif |
| |
| /* device driver for platform bus bits */ |
| |
| static struct platform_driver s3c24xx_i2c_driver = { |
| .probe = s3c24xx_i2c_probe, |
| .remove = s3c24xx_i2c_remove, |
| .id_table = s3c24xx_driver_ids, |
| .driver = { |
| .name = "s3c-i2c", |
| .pm = S3C24XX_DEV_PM_OPS, |
| .of_match_table = of_match_ptr(s3c24xx_i2c_match), |
| }, |
| }; |
| |
| static int __init i2c_adap_s3c_init(void) |
| { |
| #ifdef CONFIG_CPU_IDLE |
| exynos_pm_register_notifier(&s3c24xx_i2c_notifier_block); |
| #endif |
| return platform_driver_register(&s3c24xx_i2c_driver); |
| } |
| subsys_initcall(i2c_adap_s3c_init); |
| |
| static void __exit i2c_adap_s3c_exit(void) |
| { |
| platform_driver_unregister(&s3c24xx_i2c_driver); |
| } |
| module_exit(i2c_adap_s3c_exit); |
| |
| MODULE_DESCRIPTION("S3C24XX I2C Bus driver"); |
| MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>"); |
| MODULE_LICENSE("GPL"); |