Commit c3449f73 authored by Wolfram Sang's avatar Wolfram Sang Committed by Wolfram Sang
Browse files

i2c: sh_mobile: add helper to check frequency calculations 



Because we will add a second formula soon, put the sanity checks for the
computed results into a separate function.

Signed-off-by: default avatarWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
parent 023c22fd

drivers/i2c/busses/i2c-sh_mobile.c

+27 −22
Original line number Diff line number Diff line
@@ -246,11 +246,36 @@ static u32 sh_mobile_i2c_icch(unsigned long count_khz, u32 tHIGH, u32 tf) 
	return (((count_khz * (tHIGH + tf)) + 5000) / 10000);

}



static int sh_mobile_i2c_check_timing(struct sh_mobile_i2c_data *pd)

{

	u16 max_val = pd->flags & IIC_FLAG_HAS_ICIC67 ? 0x1ff : 0xff;



	if (pd->iccl > max_val || pd->icch > max_val) {

		dev_err(pd->dev, "timing values out of range: L/H=0x%x/0x%x\n",

			pd->iccl, pd->icch);

		return -EINVAL;

	}



	/* one more bit of ICCL in ICIC */

	if (pd->iccl & 0x100)

		pd->icic |= ICIC_ICCLB8;

	else

		pd->icic &= ~ICIC_ICCLB8;



	/* one more bit of ICCH in ICIC */

	if (pd->icch & 0x100)

		pd->icic |= ICIC_ICCHB8;

	else

		pd->icic &= ~ICIC_ICCHB8;



	dev_dbg(pd->dev, "timing values: L/H=0x%x/0x%x\n", pd->iccl, pd->icch);

	return 0;

}



static int sh_mobile_i2c_init(struct sh_mobile_i2c_data *pd)

{

	unsigned long i2c_clk_khz;

	u32 tHIGH, tLOW, tf;

	uint16_t max_val;



	i2c_clk_khz = clk_get_rate(pd->clk) / 1000 / pd->clks_per_count;
@@ -271,27 +296,7 @@ static int sh_mobile_i2c_init(struct sh_mobile_i2c_data *pd) 
	pd->iccl = sh_mobile_i2c_iccl(i2c_clk_khz, tLOW, tf);

	pd->icch = sh_mobile_i2c_icch(i2c_clk_khz, tHIGH, tf);



	max_val = pd->flags & IIC_FLAG_HAS_ICIC67 ? 0x1ff : 0xff;

	if (pd->iccl > max_val || pd->icch > max_val) {

		dev_err(pd->dev, "timing values out of range: L/H=0x%x/0x%x\n",

			pd->iccl, pd->icch);

		return -EINVAL;

	}



	/* one more bit of ICCL in ICIC */

	if (pd->iccl & 0x100)

		pd->icic |= ICIC_ICCLB8;

	else

		pd->icic &= ~ICIC_ICCLB8;



	/* one more bit of ICCH in ICIC */

	if (pd->icch & 0x100)

		pd->icic |= ICIC_ICCHB8;

	else

		pd->icic &= ~ICIC_ICCHB8;



	dev_dbg(pd->dev, "timing values: L/H=0x%x/0x%x\n", pd->iccl, pd->icch);

	return 0;

	return sh_mobile_i2c_check_timing(pd);

}



static unsigned char i2c_op(struct sh_mobile_i2c_data *pd,

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