summaryrefslogtreecommitdiff
path: root/drivers/i2c
diff options
context:
space:
mode:
authorMagnus Damm <damm@igel.co.jp>2008-10-31 14:20:55 +0300
committerPaul Mundt <lethal@linux-sh.org>2008-12-22 12:42:51 +0300
commita5616bd0f19730a780c354110454ce37209f1ded (patch)
tree367e0b2d8be763d40323c2c30e3d00a49df54a08 /drivers/i2c
parentf2eb0109fb4268505b0737cfe661542eb6151907 (diff)
downloadlinux-a5616bd0f19730a780c354110454ce37209f1ded.tar.xz
sh: sh_mobile i2c clock framework support
Add clock framework support to the sh_mobile i2c driver and adjust the processor specific code accordingly. Signed-off-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-sh_mobile.c73
1 files changed, 36 insertions, 37 deletions
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index 3384a717fec0..6c3d60b939bf 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -160,9 +160,39 @@ struct sh_mobile_i2c_data {
static void activate_ch(struct sh_mobile_i2c_data *pd)
{
+ unsigned long i2c_clk;
+ u_int32_t num;
+ u_int32_t denom;
+ u_int32_t tmp;
+
/* Make sure the clock is enabled */
clk_enable(pd->clk);
+ /* Get clock rate after clock is enabled */
+ i2c_clk = clk_get_rate(pd->clk);
+
+ /* Calculate the value for iccl. From the data sheet:
+ * iccl = (p clock / transfer rate) * (L / (L + H))
+ * where L and H are the SCL low/high ratio (5/4 in this case).
+ * We also round off the result.
+ */
+ num = i2c_clk * 5;
+ denom = NORMAL_SPEED * 9;
+ tmp = num * 10 / denom;
+ if (tmp % 10 >= 5)
+ pd->iccl = (u_int8_t)((num/denom) + 1);
+ else
+ pd->iccl = (u_int8_t)(num/denom);
+
+ /* Calculate the value for icch. From the data sheet:
+ icch = (p clock / transfer rate) * (H / (L + H)) */
+ num = i2c_clk * 4;
+ tmp = num * 10 / denom;
+ if (tmp % 10 >= 5)
+ pd->icch = (u_int8_t)((num/denom) + 1);
+ else
+ pd->icch = (u_int8_t)(num/denom);
+
/* Enable channel and configure rx ack */
iowrite8(ioread8(ICCR(pd)) | ICCR_ICE, ICCR(pd));
@@ -459,40 +489,6 @@ static struct i2c_algorithm sh_mobile_i2c_algorithm = {
.master_xfer = sh_mobile_i2c_xfer,
};
-static void sh_mobile_i2c_setup_channel(struct platform_device *dev)
-{
- struct sh_mobile_i2c_data *pd = platform_get_drvdata(dev);
- unsigned long peripheral_clk = clk_get_rate(pd->clk);
- u_int32_t num;
- u_int32_t denom;
- u_int32_t tmp;
-
- spin_lock_init(&pd->lock);
- init_waitqueue_head(&pd->wait);
-
- /* Calculate the value for iccl. From the data sheet:
- * iccl = (p clock / transfer rate) * (L / (L + H))
- * where L and H are the SCL low/high ratio (5/4 in this case).
- * We also round off the result.
- */
- num = peripheral_clk * 5;
- denom = NORMAL_SPEED * 9;
- tmp = num * 10 / denom;
- if (tmp % 10 >= 5)
- pd->iccl = (u_int8_t)((num/denom) + 1);
- else
- pd->iccl = (u_int8_t)(num/denom);
-
- /* Calculate the value for icch. From the data sheet:
- icch = (p clock / transfer rate) * (H / (L + H)) */
- num = peripheral_clk * 4;
- tmp = num * 10 / denom;
- if (tmp % 10 >= 5)
- pd->icch = (u_int8_t)((num/denom) + 1);
- else
- pd->icch = (u_int8_t)(num/denom);
-}
-
static int sh_mobile_i2c_hook_irqs(struct platform_device *dev, int hook)
{
struct resource *res;
@@ -533,6 +529,7 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
struct sh_mobile_i2c_data *pd;
struct i2c_adapter *adap;
struct resource *res;
+ char clk_name[8];
int size;
int ret;
@@ -542,9 +539,10 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
return -ENOMEM;
}
- pd->clk = clk_get(&dev->dev, "peripheral_clk");
+ snprintf(clk_name, sizeof(clk_name), "i2c%d", dev->id);
+ pd->clk = clk_get(&dev->dev, clk_name);
if (IS_ERR(pd->clk)) {
- dev_err(&dev->dev, "cannot get peripheral clock\n");
+ dev_err(&dev->dev, "cannot get clock \"%s\"\n", clk_name);
ret = PTR_ERR(pd->clk);
goto err;
}
@@ -586,7 +584,8 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
strlcpy(adap->name, dev->name, sizeof(adap->name));
- sh_mobile_i2c_setup_channel(dev);
+ spin_lock_init(&pd->lock);
+ init_waitqueue_head(&pd->wait);
ret = i2c_add_numbered_adapter(adap);
if (ret < 0) {