From a5616bd0f19730a780c354110454ce37209f1ded Mon Sep 17 00:00:00 2001 From: Magnus Damm Date: Fri, 31 Oct 2008 20:20:55 +0900 Subject: 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 Signed-off-by: Paul Mundt --- drivers/i2c/busses/i2c-sh_mobile.c | 73 +++++++++++++++++++------------------- 1 file changed, 36 insertions(+), 37 deletions(-) (limited to 'drivers') diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c index 3384a717fec..6c3d60b939b 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) { -- cgit v1.2.3