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path: root/drivers/i2c/busses/i2c-s3c2410.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-s3c2410.c')
-rw-r--r--drivers/i2c/busses/i2c-s3c2410.c544
1 files changed, 358 insertions, 186 deletions
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index 4c171808168..e828a1dba0e 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -31,20 +31,67 @@
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/clk.h>
#include <linux/cpufreq.h>
#include <linux/slab.h>
#include <linux/io.h>
-#include <linux/of_i2c.h>
+#include <linux/of.h>
#include <linux/of_gpio.h>
+#include <linux/pinctrl/consumer.h>
#include <asm/irq.h>
-#include <plat/regs-iic.h>
-#include <plat/iic.h>
+#include <linux/platform_data/i2c-s3c2410.h>
+
+/* 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 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_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)
+
+/* 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)
+
+/* 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,
@@ -53,14 +100,9 @@ enum s3c24xx_i2c_state {
STATE_STOP
};
-enum s3c24xx_i2c_type {
- TYPE_S3C2410,
- TYPE_S3C2440,
-};
-
struct s3c24xx_i2c {
- spinlock_t lock;
wait_queue_head_t wait;
+ kernel_ulong_t quirks;
unsigned int suspended:1;
struct i2c_msg *msg;
@@ -77,36 +119,61 @@ struct s3c24xx_i2c {
void __iomem *regs;
struct clk *clk;
struct device *dev;
- struct resource *ioarea;
struct i2c_adapter adap;
struct s3c2410_platform_i2c *pdata;
int gpios[2];
-#ifdef CONFIG_CPU_FREQ
+ struct pinctrl *pctrl;
+#if defined(CONFIG_ARM_S3C24XX_CPUFREQ)
struct notifier_block freq_transition;
#endif
};
-/* default platform data removed, dev should always carry data. */
+static 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,
+ }, { },
+};
+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-hdmiphy-i2c",
+ .data = (void *)(QUIRK_S3C2440 | QUIRK_HDMIPHY | QUIRK_NO_GPIO) },
+ { .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
-/* s3c24xx_i2c_is2440()
+/* s3c24xx_get_device_quirks
*
- * return true is this is an s3c2440
+ * Get controller type either from device tree or platform device variant.
*/
-static inline int s3c24xx_i2c_is2440(struct s3c24xx_i2c *i2c)
+static inline kernel_ulong_t s3c24xx_get_device_quirks(struct platform_device *pdev)
{
- struct platform_device *pdev = to_platform_device(i2c->dev);
- enum s3c24xx_i2c_type type;
-
-#ifdef CONFIG_OF
- if (i2c->dev->of_node)
- return of_device_is_compatible(i2c->dev->of_node,
- "samsung,s3c2440-i2c");
-#endif
+ 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;
+ }
- type = platform_get_device_id(pdev)->driver_data;
- return type == TYPE_S3C2440;
+ return platform_get_device_id(pdev)->driver_data;
}
/* s3c24xx_i2c_master_complete
@@ -126,7 +193,8 @@ static inline void s3c24xx_i2c_master_complete(struct s3c24xx_i2c *i2c, int ret)
if (ret)
i2c->msg_idx = ret;
- wake_up(&i2c->wait);
+ if (!(i2c->quirks & QUIRK_POLL))
+ wake_up(&i2c->wait);
}
static inline void s3c24xx_i2c_disable_ack(struct s3c24xx_i2c *i2c)
@@ -163,6 +231,22 @@ static inline void s3c24xx_i2c_enable_irq(struct s3c24xx_i2c *i2c)
writel(tmp | S3C2410_IICCON_IRQEN, i2c->regs + S3C2410_IICCON);
}
+static bool is_ack(struct s3c24xx_i2c *i2c)
+{
+ int tries;
+
+ for (tries = 50; tries; --tries) {
+ if (readl(i2c->regs + S3C2410_IICCON)
+ & S3C2410_IICCON_IRQPEND) {
+ if (!(readl(i2c->regs + S3C2410_IICSTAT)
+ & S3C2410_IICSTAT_LASTBIT))
+ return true;
+ }
+ usleep_range(1000, 2000);
+ }
+ dev_err(i2c->dev, "ack was not recieved\n");
+ return false;
+}
/* s3c24xx_i2c_message_start
*
@@ -188,7 +272,7 @@ static void s3c24xx_i2c_message_start(struct s3c24xx_i2c *i2c,
if (msg->flags & I2C_M_REV_DIR_ADDR)
addr ^= 1;
- /* todo - check for wether ack wanted or not */
+ /* todo - check for whether ack wanted or not */
s3c24xx_i2c_enable_ack(i2c);
iiccon = readl(i2c->regs + S3C2410_IICCON);
@@ -207,6 +291,16 @@ static void s3c24xx_i2c_message_start(struct s3c24xx_i2c *i2c,
stat |= S3C2410_IICSTAT_START;
writel(stat, i2c->regs + S3C2410_IICSTAT);
+
+ if (i2c->quirks & QUIRK_POLL) {
+ while ((i2c->msg_num != 0) && is_ack(i2c)) {
+ 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");
+ }
+ }
}
static inline void s3c24xx_i2c_stop(struct s3c24xx_i2c *i2c, int ret)
@@ -215,8 +309,47 @@ static inline void s3c24xx_i2c_stop(struct s3c24xx_i2c *i2c, int ret)
dev_dbg(i2c->dev, "STOP\n");
- /* stop the transfer */
- iicstat &= ~S3C2410_IICSTAT_START;
+ /*
+ * 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;
@@ -245,6 +378,12 @@ static inline int is_lastmsg(struct s3c24xx_i2c *i2c)
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;
}
@@ -377,13 +516,16 @@ static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat)
case STATE_READ:
/* we have a byte of data in the data register, do
- * something with it, and then work out wether we are
+ * 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 */
@@ -459,6 +601,31 @@ static irqreturn_t s3c24xx_i2c_irq(int irqno, void *dev_id)
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
*
@@ -482,6 +649,60 @@ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c)
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");
+}
+
/* s3c24xx_i2c_doxfer
*
* this starts an i2c transfer
@@ -490,8 +711,7 @@ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c)
static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c,
struct i2c_msg *msgs, int num)
{
- unsigned long iicstat, timeout;
- int spins = 20;
+ unsigned long timeout;
int ret;
if (i2c->suspended)
@@ -504,8 +724,6 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c,
goto out;
}
- spin_lock_irq(&i2c->lock);
-
i2c->msg = msgs;
i2c->msg_num = num;
i2c->msg_ptr = 0;
@@ -514,7 +732,15 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c,
s3c24xx_i2c_enable_irq(i2c);
s3c24xx_i2c_message_start(i2c, msgs);
- spin_unlock_irq(&i2c->lock);
+
+ if (i2c->quirks & QUIRK_POLL) {
+ ret = i2c->msg_idx;
+
+ if (ret != num)
+ dev_dbg(i2c->dev, "incomplete xfer (%d)\n", ret);
+
+ goto out;
+ }
timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
@@ -528,26 +754,17 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c,
else if (ret != num)
dev_dbg(i2c->dev, "incomplete xfer (%d)\n", ret);
- /* ensure the stop has been through the bus */
-
- dev_dbg(i2c->dev, "waiting for bus idle\n");
-
- /* first, try busy waiting briefly */
- do {
- cpu_relax();
- iicstat = readl(i2c->regs + S3C2410_IICSTAT);
- } while ((iicstat & S3C2410_IICSTAT_START) && --spins);
+ /* For QUIRK_HDMIPHY, bus is already disabled */
+ if (i2c->quirks & QUIRK_HDMIPHY)
+ goto out;
- /* if that timed out sleep */
- if (!spins) {
- msleep(1);
- iicstat = readl(i2c->regs + S3C2410_IICSTAT);
- }
+ s3c24xx_i2c_wait_idle(i2c);
- if (iicstat & S3C2410_IICSTAT_START)
- dev_warn(i2c->dev, "timeout waiting for bus idle\n");
+ s3c24xx_i2c_disable_bus(i2c);
out:
+ i2c->state = STATE_IDLE;
+
return ret;
}
@@ -564,14 +781,16 @@ static int s3c24xx_i2c_xfer(struct i2c_adapter *adap,
int retry;
int ret;
- clk_enable(i2c->clk);
+ pm_runtime_get_sync(&adap->dev);
+ clk_prepare_enable(i2c->clk);
for (retry = 0; retry < adap->retries; retry++) {
ret = s3c24xx_i2c_doxfer(i2c, msgs, num);
if (ret != -EAGAIN) {
- clk_disable(i2c->clk);
+ clk_disable_unprepare(i2c->clk);
+ pm_runtime_put(&adap->dev);
return ret;
}
@@ -580,14 +799,16 @@ static int s3c24xx_i2c_xfer(struct i2c_adapter *adap,
udelay(100);
}
- clk_disable(i2c->clk);
+ clk_disable_unprepare(i2c->clk);
+ pm_runtime_put(&adap->dev);
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_PROTOCOL_MANGLING;
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_NOSTART |
+ I2C_FUNC_PROTOCOL_MANGLING;
}
/* i2c bus registration info */
@@ -670,9 +891,12 @@ static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got)
if (div1 == 512)
iiccon |= S3C2410_IICCON_TXDIV_512;
+ if (i2c->quirks & QUIRK_POLL)
+ iiccon |= S3C2410_IICCON_SCALE(2);
+
writel(iiccon, i2c->regs + S3C2410_IICCON);
- if (s3c24xx_i2c_is2440(i2c)) {
+ if (i2c->quirks & QUIRK_S3C2440) {
unsigned long sda_delay;
if (pdata->sda_delay) {
@@ -692,7 +916,7 @@ static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got)
return 0;
}
-#ifdef CONFIG_CPU_FREQ
+#if defined(CONFIG_ARM_S3C24XX_CPUFREQ)
#define freq_to_i2c(_n) container_of(_n, struct s3c24xx_i2c, freq_transition)
@@ -700,7 +924,6 @@ static int s3c24xx_i2c_cpufreq_transition(struct notifier_block *nb,
unsigned long val, void *data)
{
struct s3c24xx_i2c *i2c = freq_to_i2c(nb);
- unsigned long flags;
unsigned int got;
int delta_f;
int ret;
@@ -714,9 +937,9 @@ static int s3c24xx_i2c_cpufreq_transition(struct notifier_block *nb,
if ((val == CPUFREQ_POSTCHANGE && delta_f < 0) ||
(val == CPUFREQ_PRECHANGE && delta_f > 0)) {
- spin_lock_irqsave(&i2c->lock, flags);
+ i2c_lock_adapter(&i2c->adap);
ret = s3c24xx_i2c_clockrate(i2c, &got);
- spin_unlock_irqrestore(&i2c->lock, flags);
+ i2c_unlock_adapter(&i2c->adap);
if (ret < 0)
dev_err(i2c->dev, "cannot find frequency\n");
@@ -757,12 +980,16 @@ 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) {
@@ -781,6 +1008,10 @@ free_gpio:
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]);
}
@@ -802,7 +1033,6 @@ static void s3c24xx_i2c_dt_gpio_free(struct s3c24xx_i2c *i2c)
static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
{
- unsigned long iicon = S3C2410_IICCON_IRQEN | S3C2410_IICCON_ACKEN;
struct s3c2410_platform_i2c *pdata;
unsigned int freq;
@@ -810,26 +1040,18 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
pdata = i2c->pdata;
- /* inititalise the gpio */
-
- if (pdata->cfg_gpio)
- pdata->cfg_gpio(to_platform_device(i2c->dev));
- else
- if (s3c24xx_i2c_parse_dt_gpio(i2c))
- return -EINVAL;
-
/* write slave address */
writeb(pdata->slave_addr, i2c->regs + S3C2410_IICADD);
dev_info(i2c->dev, "slave address 0x%02x\n", pdata->slave_addr);
- writel(iicon, i2c->regs + S3C2410_IICCON);
+ 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) {
- writel(0, i2c->regs + S3C2410_IICCON);
dev_err(i2c->dev, "cannot meet bus frequency required\n");
return -EINVAL;
}
@@ -837,7 +1059,8 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
/* todo - check that the i2c lines aren't being dragged anywhere */
dev_info(i2c->dev, "bus frequency set to %d KHz\n", freq);
- dev_dbg(i2c->dev, "S3C2410_IICCON=0x%02lx\n", iicon);
+ dev_dbg(i2c->dev, "S3C2410_IICCON=0x%02x\n",
+ readl(i2c->regs + S3C2410_IICCON));
return 0;
}
@@ -883,25 +1106,22 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
int ret;
if (!pdev->dev.of_node) {
- pdata = pdev->dev.platform_data;
+ pdata = dev_get_platdata(&pdev->dev);
if (!pdata) {
dev_err(&pdev->dev, "no platform data\n");
return -EINVAL;
}
}
- i2c = kzalloc(sizeof(struct s3c24xx_i2c), GFP_KERNEL);
- if (!i2c) {
- dev_err(&pdev->dev, "no memory for state\n");
+ 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) {
- ret = -ENOMEM;
- goto err_noclk;
- }
+ if (!i2c->pdata)
+ return -ENOMEM;
+ i2c->quirks = s3c24xx_get_device_quirks(pdev);
if (pdata)
memcpy(i2c->pdata, pdata, sizeof(*pdata));
else
@@ -911,88 +1131,82 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
i2c->adap.owner = THIS_MODULE;
i2c->adap.algo = &s3c24xx_i2c_algorithm;
i2c->adap.retries = 2;
- i2c->adap.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+ i2c->adap.class = I2C_CLASS_HWMON | I2C_CLASS_SPD | I2C_CLASS_DEPRECATED;
i2c->tx_setup = 50;
- spin_lock_init(&i2c->lock);
init_waitqueue_head(&i2c->wait);
/* find the clock and enable it */
i2c->dev = &pdev->dev;
- i2c->clk = clk_get(&pdev->dev, "i2c");
+ i2c->clk = devm_clk_get(&pdev->dev, "i2c");
if (IS_ERR(i2c->clk)) {
dev_err(&pdev->dev, "cannot get clock\n");
- ret = -ENOENT;
- goto err_noclk;
+ return -ENOENT;
}
dev_dbg(&pdev->dev, "clock source %p\n", i2c->clk);
- clk_enable(i2c->clk);
/* map the registers */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (res == NULL) {
- dev_err(&pdev->dev, "cannot find 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 IO\n");
- ret = -ENXIO;
- goto err_clk;
- }
-
- i2c->regs = ioremap(res->start, resource_size(res));
+ i2c->regs = devm_ioremap_resource(&pdev->dev, res);
- if (i2c->regs == NULL) {
- dev_err(&pdev->dev, "cannot map IO\n");
- ret = -ENXIO;
- goto err_ioarea;
- }
+ if (IS_ERR(i2c->regs))
+ return PTR_ERR(i2c->regs);
- dev_dbg(&pdev->dev, "registers %p (%p, %p)\n",
- i2c->regs, i2c->ioarea, res);
+ 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;
+ }
+
/* initialise the i2c controller */
+ clk_prepare_enable(i2c->clk);
ret = s3c24xx_i2c_init(i2c);
- if (ret != 0)
- goto err_iomap;
-
+ clk_disable_unprepare(i2c->clk);
+ if (ret != 0) {
+ dev_err(&pdev->dev, "I2C controller init failed\n");
+ return ret;
+ }
/* find the IRQ for this unit (note, this relies on the init call to
* ensure no current IRQs pending
*/
- i2c->irq = ret = platform_get_irq(pdev, 0);
- if (ret <= 0) {
- dev_err(&pdev->dev, "cannot find IRQ\n");
- goto err_iomap;
- }
+ if (!(i2c->quirks & QUIRK_POLL)) {
+ i2c->irq = ret = platform_get_irq(pdev, 0);
+ if (ret <= 0) {
+ dev_err(&pdev->dev, "cannot find IRQ\n");
+ return ret;
+ }
- ret = request_irq(i2c->irq, s3c24xx_i2c_irq, 0,
- dev_name(&pdev->dev), i2c);
+ 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);
- goto err_iomap;
+ if (ret != 0) {
+ dev_err(&pdev->dev, "cannot claim IRQ %d\n", i2c->irq);
+ return ret;
+ }
}
ret = s3c24xx_i2c_register_cpufreq(i2c);
if (ret < 0) {
dev_err(&pdev->dev, "failed to register cpufreq notifier\n");
- goto err_irq;
+ return ret;
}
/* Note, previous versions of the driver used i2c_add_adapter()
@@ -1007,36 +1221,17 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
ret = i2c_add_numbered_adapter(&i2c->adap);
if (ret < 0) {
dev_err(&pdev->dev, "failed to add bus to i2c core\n");
- goto err_cpufreq;
+ s3c24xx_i2c_deregister_cpufreq(i2c);
+ return ret;
}
- of_i2c_register_devices(&i2c->adap);
platform_set_drvdata(pdev, i2c);
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_enable(&i2c->adap.dev);
+
dev_info(&pdev->dev, "%s: S3C I2C adapter\n", dev_name(&i2c->adap.dev));
- clk_disable(i2c->clk);
return 0;
-
- err_cpufreq:
- s3c24xx_i2c_deregister_cpufreq(i2c);
-
- 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(i2c->clk);
- clk_put(i2c->clk);
-
- err_noclk:
- kfree(i2c);
- return ret;
}
/* s3c24xx_i2c_remove
@@ -1048,25 +1243,20 @@ static int s3c24xx_i2c_remove(struct platform_device *pdev)
{
struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev);
+ pm_runtime_disable(&i2c->adap.dev);
+ pm_runtime_disable(&pdev->dev);
+
s3c24xx_i2c_deregister_cpufreq(i2c);
i2c_del_adapter(&i2c->adap);
- free_irq(i2c->irq, i2c);
-
- clk_disable(i2c->clk);
- clk_put(i2c->clk);
-
- iounmap(i2c->regs);
- release_resource(i2c->ioarea);
- s3c24xx_i2c_dt_gpio_free(i2c);
- kfree(i2c->ioarea);
- kfree(i2c);
+ if (pdev->dev.of_node && IS_ERR(i2c->pctrl))
+ s3c24xx_i2c_dt_gpio_free(i2c);
return 0;
}
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
static int s3c24xx_i2c_suspend_noirq(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
@@ -1082,17 +1272,21 @@ static int s3c24xx_i2c_resume(struct device *dev)
struct platform_device *pdev = to_platform_device(dev);
struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev);
- i2c->suspended = 0;
- clk_enable(i2c->clk);
+ clk_prepare_enable(i2c->clk);
s3c24xx_i2c_init(i2c);
- clk_disable(i2c->clk);
+ clk_disable_unprepare(i2c->clk);
+ i2c->suspended = 0;
return 0;
}
+#endif
+#ifdef CONFIG_PM
static const struct dev_pm_ops s3c24xx_i2c_dev_pm_ops = {
+#ifdef CONFIG_PM_SLEEP
.suspend_noirq = s3c24xx_i2c_suspend_noirq,
.resume = s3c24xx_i2c_resume,
+#endif
};
#define S3C24XX_DEV_PM_OPS (&s3c24xx_i2c_dev_pm_ops)
@@ -1102,28 +1296,6 @@ static const struct dev_pm_ops s3c24xx_i2c_dev_pm_ops = {
/* device driver for platform bus bits */
-static struct platform_device_id s3c24xx_driver_ids[] = {
- {
- .name = "s3c2410-i2c",
- .driver_data = TYPE_S3C2410,
- }, {
- .name = "s3c2440-i2c",
- .driver_data = TYPE_S3C2440,
- }, { },
-};
-MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids);
-
-#ifdef CONFIG_OF
-static const struct of_device_id s3c24xx_i2c_match[] = {
- { .compatible = "samsung,s3c2410-i2c" },
- { .compatible = "samsung,s3c2440-i2c" },
- {},
-};
-MODULE_DEVICE_TABLE(of, s3c24xx_i2c_match);
-#else
-#define s3c24xx_i2c_match NULL
-#endif
-
static struct platform_driver s3c24xx_i2c_driver = {
.probe = s3c24xx_i2c_probe,
.remove = s3c24xx_i2c_remove,
@@ -1132,7 +1304,7 @@ static struct platform_driver s3c24xx_i2c_driver = {
.owner = THIS_MODULE,
.name = "s3c-i2c",
.pm = S3C24XX_DEV_PM_OPS,
- .of_match_table = s3c24xx_i2c_match,
+ .of_match_table = of_match_ptr(s3c24xx_i2c_match),
},
};