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sh: sh_mobile i2c clock framework support

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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>
This commit is contained in:
Magnus Damm
2008-10-31 20:20:55 +09:00
committed by Paul Mundt
parent f2eb0109fb
commit a5616bd0f1
5 changed files with 41 additions and 42 deletions
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73
drivers/i2c/busses/i2c-sh_mobile.c
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@@ -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) {