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-rw-r--r--drivers/i2c/busses/i2c-bfin-twi.c35
-rw-r--r--drivers/i2c/busses/i2c-gpio.c9
-rw-r--r--drivers/i2c/busses/i2c-s3c2410.c129
3 files changed, 144 insertions, 29 deletions
diff --git a/drivers/i2c/busses/i2c-bfin-twi.c b/drivers/i2c/busses/i2c-bfin-twi.c
index 48d084bdf7c..3c855ff2992 100644
--- a/drivers/i2c/busses/i2c-bfin-twi.c
+++ b/drivers/i2c/busses/i2c-bfin-twi.c
@@ -49,6 +49,8 @@ struct bfin_twi_iface {
struct i2c_msg *pmsg;
int msg_num;
int cur_msg;
+ u16 saved_clkdiv;
+ u16 saved_control;
void __iomem *regs_base;
};
@@ -565,32 +567,43 @@ static u32 bfin_twi_functionality(struct i2c_adapter *adap)
I2C_FUNC_I2C;
}
-
static struct i2c_algorithm bfin_twi_algorithm = {
.master_xfer = bfin_twi_master_xfer,
.smbus_xfer = bfin_twi_smbus_xfer,
.functionality = bfin_twi_functionality,
};
-
-static int i2c_bfin_twi_suspend(struct platform_device *dev, pm_message_t state)
+static int i2c_bfin_twi_suspend(struct platform_device *pdev, pm_message_t state)
{
- struct bfin_twi_iface *iface = platform_get_drvdata(dev);
+ struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
+
+ iface->saved_clkdiv = read_CLKDIV(iface);
+ iface->saved_control = read_CONTROL(iface);
+
+ free_irq(iface->irq, iface);
/* Disable TWI */
- write_CONTROL(iface, read_CONTROL(iface) & ~TWI_ENA);
- SSYNC();
+ write_CONTROL(iface, iface->saved_control & ~TWI_ENA);
return 0;
}
-static int i2c_bfin_twi_resume(struct platform_device *dev)
+static int i2c_bfin_twi_resume(struct platform_device *pdev)
{
- struct bfin_twi_iface *iface = platform_get_drvdata(dev);
+ struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
- /* Enable TWI */
- write_CONTROL(iface, read_CONTROL(iface) | TWI_ENA);
- SSYNC();
+ int rc = request_irq(iface->irq, bfin_twi_interrupt_entry,
+ IRQF_DISABLED, pdev->name, iface);
+ if (rc) {
+ dev_err(&pdev->dev, "Can't get IRQ %d !\n", iface->irq);
+ return -ENODEV;
+ }
+
+ /* Resume TWI interface clock as specified */
+ write_CLKDIV(iface, iface->saved_clkdiv);
+
+ /* Resume TWI */
+ write_CONTROL(iface, iface->saved_control);
return 0;
}
diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c
index 79b455a1f09..32104eac8d3 100644
--- a/drivers/i2c/busses/i2c-gpio.c
+++ b/drivers/i2c/busses/i2c-gpio.c
@@ -77,7 +77,7 @@ static int i2c_gpio_getscl(void *data)
return gpio_get_value(pdata->scl_pin);
}
-static int __init i2c_gpio_probe(struct platform_device *pdev)
+static int __devinit i2c_gpio_probe(struct platform_device *pdev)
{
struct i2c_gpio_platform_data *pdata;
struct i2c_algo_bit_data *bit_data;
@@ -174,7 +174,7 @@ err_alloc_adap:
return ret;
}
-static int __exit i2c_gpio_remove(struct platform_device *pdev)
+static int __devexit i2c_gpio_remove(struct platform_device *pdev)
{
struct i2c_gpio_platform_data *pdata;
struct i2c_adapter *adap;
@@ -196,14 +196,15 @@ static struct platform_driver i2c_gpio_driver = {
.name = "i2c-gpio",
.owner = THIS_MODULE,
},
- .remove = __exit_p(i2c_gpio_remove),
+ .probe = i2c_gpio_probe,
+ .remove = __devexit_p(i2c_gpio_remove),
};
static int __init i2c_gpio_init(void)
{
int ret;
- ret = platform_driver_probe(&i2c_gpio_driver, i2c_gpio_probe);
+ ret = platform_driver_register(&i2c_gpio_driver);
if (ret)
printk(KERN_ERR "i2c-gpio: probe failed: %d\n", ret);
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index 007390ad981..4864723c742 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -33,6 +33,7 @@
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
+#include <linux/cpufreq.h>
#include <asm/hardware.h>
#include <asm/irq.h>
@@ -64,6 +65,7 @@ struct s3c24xx_i2c {
unsigned int tx_setup;
enum s3c24xx_i2c_state state;
+ unsigned long clkrate;
void __iomem *regs;
struct clk *clk;
@@ -71,6 +73,10 @@ struct s3c24xx_i2c {
struct resource *irq;
struct resource *ioarea;
struct i2c_adapter adap;
+
+#ifdef CONFIG_CPU_FREQ
+ struct notifier_block freq_transition;
+#endif
};
/* default platform data to use if not supplied in the platform_device
@@ -501,6 +507,9 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, struct i2c_msg *msgs, int
unsigned long timeout;
int ret;
+ if (!readl(i2c->regs + S3C2410_IICCON) & S3C2410_IICCON_IRQEN)
+ return -EIO;
+
ret = s3c24xx_i2c_set_master(i2c);
if (ret != 0) {
dev_err(i2c->dev, "cannot get bus (error %d)\n", ret);
@@ -636,27 +645,28 @@ static inline int freq_acceptable(unsigned int freq, unsigned int wanted)
return (diff >= -2 && diff <= 2);
}
-/* s3c24xx_i2c_getdivisor
+/* 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_getdivisor(struct s3c24xx_i2c *i2c,
- struct s3c2410_platform_i2c *pdata,
- unsigned long *iicon,
- unsigned int *got)
+static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got)
{
+ struct s3c2410_platform_i2c *pdata;
unsigned long clkin = clk_get_rate(i2c->clk);
-
unsigned int divs, div1;
+ u32 iiccon;
int freq;
int start, end;
+ i2c->clkrate = clkin;
+
+ pdata = s3c24xx_i2c_get_platformdata(i2c->adap.dev.parent);
clkin /= 1000; /* clkin now in KHz */
- dev_dbg(i2c->dev, "pdata %p, freq %lu %lu..%lu\n",
+ dev_dbg(i2c->dev, "pdata %p, freq %lu %lu..%lu\n",
pdata, pdata->bus_freq, pdata->min_freq, pdata->max_freq);
if (pdata->bus_freq != 0) {
@@ -688,11 +698,79 @@ static int s3c24xx_i2c_getdivisor(struct s3c24xx_i2c *i2c,
found:
*got = freq;
- *iicon |= (divs-1);
- *iicon |= (div1 == 512) ? S3C2410_IICCON_TXDIV_512 : 0;
+
+ 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);
+
+ return 0;
+}
+
+#ifdef CONFIG_CPU_FREQ
+
+#define freq_to_i2c(_n) container_of(_n, struct s3c24xx_i2c, freq_transition)
+
+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;
+
+ delta_f = clk_get_rate(i2c->clk) - i2c->clkrate;
+
+ /* if we're post-change and the input clock has slowed down
+ * or at pre-change and the clock is about to speed up, then
+ * adjust our clock rate. <0 is slow, >0 speedup.
+ */
+
+ if ((val == CPUFREQ_POSTCHANGE && delta_f < 0) ||
+ (val == CPUFREQ_PRECHANGE && delta_f > 0)) {
+ spin_lock_irqsave(&i2c->lock, flags);
+ ret = s3c24xx_i2c_clockrate(i2c, &got);
+ spin_unlock_irqrestore(&i2c->lock, flags);
+
+ if (ret < 0)
+ dev_err(i2c->dev, "cannot find frequency\n");
+ else
+ dev_info(i2c->dev, "setting freq %d\n", got);
+ }
+
+ return 0;
+}
+
+static inline int s3c24xx_i2c_register_cpufreq(struct s3c24xx_i2c *i2c)
+{
+ i2c->freq_transition.notifier_call = s3c24xx_i2c_cpufreq_transition;
+
+ return cpufreq_register_notifier(&i2c->freq_transition,
+ CPUFREQ_TRANSITION_NOTIFIER);
+}
+
+static inline void s3c24xx_i2c_deregister_cpufreq(struct s3c24xx_i2c *i2c)
+{
+ cpufreq_unregister_notifier(&i2c->freq_transition,
+ CPUFREQ_TRANSITION_NOTIFIER);
+}
+
+#else
+static inline int s3c24xx_i2c_register_cpufreq(struct s3c24xx_i2c *i2c)
+{
return 0;
}
+static inline void s3c24xx_i2c_deregister_cpufreq(struct s3c24xx_i2c *i2c)
+{
+}
+#endif
+
/* s3c24xx_i2c_init
*
* initialise the controller, set the IO lines and frequency
@@ -719,9 +797,12 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
dev_info(i2c->dev, "slave address 0x%02x\n", pdata->slave_addr);
+ writel(iicon, i2c->regs + S3C2410_IICCON);
+
/* we need to work out the divisors for the clock... */
- if (s3c24xx_i2c_getdivisor(i2c, pdata, &iicon, &freq) != 0) {
+ 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;
}
@@ -730,8 +811,6 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
dev_info(i2c->dev, "bus frequency set to %d KHz\n", freq);
dev_dbg(i2c->dev, "S3C2410_IICCON=0x%02lx\n", iicon);
-
- writel(iicon, i2c->regs + S3C2410_IICCON);
/* check for s3c2440 i2c controller */
@@ -752,9 +831,12 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
static int s3c24xx_i2c_probe(struct platform_device *pdev)
{
struct s3c24xx_i2c *i2c = &s3c24xx_i2c;
+ struct s3c2410_platform_i2c *pdata;
struct resource *res;
int ret;
+ pdata = s3c24xx_i2c_get_platformdata(&pdev->dev);
+
/* find the clock and enable it */
i2c->dev = &pdev->dev;
@@ -832,17 +914,34 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
dev_dbg(&pdev->dev, "irq resource %p (%lu)\n", res,
(unsigned long)res->start);
- ret = i2c_add_adapter(&i2c->adap);
+ ret = s3c24xx_i2c_register_cpufreq(i2c);
if (ret < 0) {
- dev_err(&pdev->dev, "failed to add bus to i2c core\n");
+ dev_err(&pdev->dev, "failed to register cpufreq notifier\n");
goto err_irq;
}
+ /* 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 = pdata->bus_num;
+
+ 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;
+ }
+
platform_set_drvdata(pdev, i2c);
dev_info(&pdev->dev, "%s: S3C I2C adapter\n", i2c->adap.dev.bus_id);
return 0;
+ err_cpufreq:
+ s3c24xx_i2c_deregister_cpufreq(i2c);
+
err_irq:
free_irq(i2c->irq->start, i2c);
@@ -870,6 +969,8 @@ static int s3c24xx_i2c_remove(struct platform_device *pdev)
{
struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev);
+ s3c24xx_i2c_deregister_cpufreq(i2c);
+
i2c_del_adapter(&i2c->adap);
free_irq(i2c->irq->start, i2c);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-15 11:09:15 +0000