From: Martin Kaiser <martin@xxxxxxxxx> commit 2636ba8fa39915c7b8d73166961ebbb4c14251cd upstream. Modify spi_imx_clkdiv_2() to return the resulting bus clock frequency when the selected clock divider is applied. Set spi_imx->spi_bus_clk to this frequency. If spi_bus_clk is unset, spi_imx_calculate_timeout() causes a division by 0. Cc: <stable@xxxxxxxxxxxxxxx> # 4.8.x Signed-off-by: Martin Kaiser <martin@xxxxxxxxx> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Fabio Estevam <fabio.estevam@xxxxxxx> --- drivers/spi/spi-imx.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index f63cb30..5cc72be 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -186,17 +186,19 @@ static unsigned int spi_imx_clkdiv_1(unsigned int fin, /* MX1, MX31, MX35, MX51 CSPI */ static unsigned int spi_imx_clkdiv_2(unsigned int fin, - unsigned int fspi) + unsigned int fspi, unsigned int *fres) { int i, div = 4; for (i = 0; i < 7; i++) { if (fspi * div >= fin) - return i; + goto out; div <<= 1; } - return 7; +out: + *fres = fin / div; + return i; } static int spi_imx_bytes_per_word(const int bpw) @@ -482,9 +484,11 @@ static int mx31_config(struct spi_device *spi, struct spi_imx_config *config) { struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER; + unsigned int clk; - reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) << + reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz, &clk) << MX31_CSPICTRL_DR_SHIFT; + spi_imx->spi_bus_clk = clk; if (is_imx35_cspi(spi_imx)) { reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT; @@ -625,9 +629,12 @@ static int mx1_config(struct spi_device *spi, struct spi_imx_config *config) { struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER; + unsigned int clk; - reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) << + reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz, &clk) << MX1_CSPICTRL_DR_SHIFT; + spi_imx->spi_bus_clk = clk; + reg |= config->bpw - 1; if (spi->mode & SPI_CPHA) -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html