diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c index 79888e6c54c2..ddf1c684bcc7 100644 --- a/drivers/spi/spi-omap2-mcspi.c +++ b/drivers/spi/spi-omap2-mcspi.c @@ -125,10 +125,12 @@ struct omap2_mcspi { struct omap2_mcspi_dma *dma_channels; struct device *dev; struct omap2_mcspi_regs ctx; + struct clk *ref_clk; int fifo_depth; bool target_aborted; unsigned int pin_dir:1; size_t max_xfer_len; + u32 ref_clk_hz; }; struct omap2_mcspi_cs { @@ -880,12 +882,12 @@ out: return count - c; } -static u32 omap2_mcspi_calc_divisor(u32 speed_hz) +static u32 omap2_mcspi_calc_divisor(u32 speed_hz, u32 ref_clk_hz) { u32 div; for (div = 0; div < 15; div++) - if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div)) + if (speed_hz >= (ref_clk_hz >> div)) return div; return 15; @@ -897,7 +899,7 @@ static int omap2_mcspi_setup_transfer(struct spi_device *spi, { struct omap2_mcspi_cs *cs = spi->controller_state; struct omap2_mcspi *mcspi; - u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0; + u32 ref_clk_hz, l = 0, clkd = 0, div, extclk = 0, clkg = 0; u8 word_len = spi->bits_per_word; u32 speed_hz = spi->max_speed_hz; @@ -911,14 +913,15 @@ static int omap2_mcspi_setup_transfer(struct spi_device *spi, if (t && t->speed_hz) speed_hz = t->speed_hz; - speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ); - if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) { - clkd = omap2_mcspi_calc_divisor(speed_hz); - speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd; + ref_clk_hz = mcspi->ref_clk_hz; + speed_hz = min_t(u32, speed_hz, ref_clk_hz); + if (speed_hz < (ref_clk_hz / OMAP2_MCSPI_MAX_DIVIDER)) { + clkd = omap2_mcspi_calc_divisor(speed_hz, ref_clk_hz); + speed_hz = ref_clk_hz >> clkd; clkg = 0; } else { - div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz; - speed_hz = OMAP2_MCSPI_MAX_FREQ / div; + div = (ref_clk_hz + speed_hz - 1) / speed_hz; + speed_hz = ref_clk_hz / div; clkd = (div - 1) & 0xf; extclk = (div - 1) >> 4; clkg = OMAP2_MCSPI_CHCONF_CLKG; @@ -1448,8 +1451,6 @@ static int omap2_mcspi_probe(struct platform_device *pdev) ctlr->cleanup = omap2_mcspi_cleanup; ctlr->target_abort = omap2_mcspi_target_abort; ctlr->dev.of_node = node; - ctlr->max_speed_hz = OMAP2_MCSPI_MAX_FREQ; - ctlr->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15; ctlr->use_gpio_descriptors = true; platform_set_drvdata(pdev, ctlr); @@ -1519,6 +1520,14 @@ static int omap2_mcspi_probe(struct platform_device *pdev) goto free_ctlr; } + mcspi->ref_clk = devm_clk_get_optional_enabled(&pdev->dev, NULL); + if (mcspi->ref_clk) + mcspi->ref_clk_hz = clk_get_rate(mcspi->ref_clk); + else + mcspi->ref_clk_hz = OMAP2_MCSPI_MAX_FREQ; + ctlr->max_speed_hz = mcspi->ref_clk_hz; + ctlr->min_speed_hz = mcspi->ref_clk_hz >> 15; + pm_runtime_use_autosuspend(&pdev->dev); pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT); pm_runtime_enable(&pdev->dev);