diff options
| author |   Wolfram Sang <wsa+renesas@sang-engineering.com> | 2017-12-18 22:58:00 +0100 |
|---|---|---|
| committer |   Wolfram Sang <wsa@the-dreams.de> | 2018-01-15 18:01:03 +0100 |
| commit | c3449f73a80b2b04a3f7ff69be871c153ea1a9fa (patch) | |
| tree | 01599dd9e2d89720de417e23d59c053337864c74 /drivers/i2c | |
| parent | i2c: sh_mobile: let RuntimePM do the clock handling (diff) | |
| download | linux-dev-c3449f73a80b2b04a3f7ff69be871c153ea1a9fa.tar.xz linux-dev-c3449f73a80b2b04a3f7ff69be871c153ea1a9fa.zip | |
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: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-sh_mobile.c | 49 |
1 files changed, 27 insertions, 22 deletions
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c index f1a9b971e2c1..b111191a449a 100644 --- a/drivers/i2c/busses/i2c-sh_mobile.c +++ b/drivers/i2c/busses/i2c-sh_mobile.c @@ -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, |