i2c: davinci: Avoid zero value of CLKH

[ 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>
This commit is contained in:
Alexander Sverdlin 2018-07-13 17:20:17 +02:00 committed by Greg Kroah-Hartman
parent ae34cbea8c
commit ca08b42d1f

View file

@ -234,12 +234,16 @@ static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev)
/*
* 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);
}