4.9-stable review patch. If anyone has any objections, please let me know.
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From: Alexander Sverdlin alexander.sverdlin@nokia.com
[ Upstream commit cc8de9a68599b261244ea453b38678229f06ada7 ]
If CLKH is set to 0 I2C clock is not generated at all, so avoid this value and stretch the clock in this case.
Signed-off-by: Alexander Sverdlin alexander.sverdlin@nokia.com Acked-by: Sekhar Nori nsekhar@ti.com Signed-off-by: Wolfram Sang wsa@the-dreams.de Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/i2c/busses/i2c-davinci.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
--- a/drivers/i2c/busses/i2c-davinci.c +++ b/drivers/i2c/busses/i2c-davinci.c @@ -234,12 +234,16 @@ static void i2c_davinci_calc_clk_divider /* * It's not always possible to have 1 to 2 ratio when d=7, so fall back * to minimal possible clkh in this case. + * + * Note: + * CLKH is not allowed to be 0, in this case I2C clock is not generated + * at all */ - if (clk >= clkl + d) { + if (clk > clkl + d) { clkh = clk - clkl - d; clkl -= d; } else { - clkh = 0; + clkh = 1; clkl = clk - (d << 1); }