From 162a31effc4182dd5a0675d9fd0336d5096e0ad3 Mon Sep 17 00:00:00 2001 From: Mason Zhang Date: Tue, 29 Jun 2021 18:08:15 +0800 Subject: [PATCH] spi: mediatek: add no_need_unprepare support This patch add no_need_unprepare support for spi, if spi src clk is MAIN PLL, it can keep the clk_prepare and will not cause low power issue. So we no need do clk_prepare/clk_unprepare in runtime pm, and it will get better performance, because clk_prepare has called mutex lock. In the same way, clk_get_rate also has called mutex lock, so we moved it to spi_probe. Signed-off-by: Mason Zhang Link: https://lore.kernel.org/r/20210629100814.21402-1-mason.zhang@mediatek.com Signed-off-by: Mark Brown --- drivers/spi/spi-mt65xx.c | 41 ++++++++++++++++++++++++++++++++++------- 1 file changed, 34 insertions(+), 7 deletions(-) diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c index 976f73b..097625d 100644 --- a/drivers/spi/spi-mt65xx.c +++ b/drivers/spi/spi-mt65xx.c @@ -90,6 +90,8 @@ struct mtk_spi_compatible { bool enhance_timing; /* some IC support DMA addr extension */ bool dma_ext; + /* some IC no need unprepare SPI clk */ + bool no_need_unprepare; }; struct mtk_spi { @@ -104,6 +106,7 @@ struct mtk_spi { struct scatterlist *tx_sgl, *rx_sgl; u32 tx_sgl_len, rx_sgl_len; const struct mtk_spi_compatible *dev_comp; + u32 spi_clk_hz; }; static const struct mtk_spi_compatible mtk_common_compat; @@ -135,6 +138,14 @@ static const struct mtk_spi_compatible mt8183_compat = { .enhance_timing = true, }; +static const struct mtk_spi_compatible mt6893_compat = { + .need_pad_sel = true, + .must_tx = true, + .enhance_timing = true, + .dma_ext = true, + .no_need_unprepare = true, +}; + /* * A piece of default chip info unless the platform * supplies it. @@ -174,6 +185,9 @@ static const struct of_device_id mtk_spi_of_match[] = { { .compatible = "mediatek,mt8192-spi", .data = (void *)&mt6765_compat, }, + { .compatible = "mediatek,mt6893-spi", + .data = (void *)&mt6893_compat, + }, {} }; MODULE_DEVICE_TABLE(of, mtk_spi_of_match); @@ -287,12 +301,11 @@ static void mtk_spi_set_cs(struct spi_device *spi, bool enable) static void mtk_spi_prepare_transfer(struct spi_master *master, struct spi_transfer *xfer) { - u32 spi_clk_hz, div, sck_time, reg_val; + u32 div, sck_time, reg_val; struct mtk_spi *mdata = spi_master_get_devdata(master); - spi_clk_hz = clk_get_rate(mdata->spi_clk); - if (xfer->speed_hz < spi_clk_hz / 2) - div = DIV_ROUND_UP(spi_clk_hz, xfer->speed_hz); + if (xfer->speed_hz < mdata->spi_clk_hz / 2) + div = DIV_ROUND_UP(mdata->spi_clk_hz, xfer->speed_hz); else div = 1; @@ -789,7 +802,12 @@ static int mtk_spi_probe(struct platform_device *pdev) goto err_put_master; } - clk_disable_unprepare(mdata->spi_clk); + mdata->spi_clk_hz = clk_get_rate(mdata->spi_clk); + + if (mdata->dev_comp->no_need_unprepare) + clk_disable(mdata->spi_clk); + else + clk_disable_unprepare(mdata->spi_clk); pm_runtime_enable(&pdev->dev); @@ -857,6 +875,9 @@ static int mtk_spi_remove(struct platform_device *pdev) mtk_spi_reset(mdata); + if (mdata->dev_comp->no_need_unprepare) + clk_unprepare(mdata->spi_clk); + return 0; } @@ -905,7 +926,10 @@ static int mtk_spi_runtime_suspend(struct device *dev) struct spi_master *master = dev_get_drvdata(dev); struct mtk_spi *mdata = spi_master_get_devdata(master); - clk_disable_unprepare(mdata->spi_clk); + if (mdata->dev_comp->no_need_unprepare) + clk_disable(mdata->spi_clk); + else + clk_disable_unprepare(mdata->spi_clk); return 0; } @@ -916,7 +940,10 @@ static int mtk_spi_runtime_resume(struct device *dev) struct mtk_spi *mdata = spi_master_get_devdata(master); int ret; - ret = clk_prepare_enable(mdata->spi_clk); + if (mdata->dev_comp->no_need_unprepare) + ret = clk_enable(mdata->spi_clk); + else + ret = clk_prepare_enable(mdata->spi_clk); if (ret < 0) { dev_err(dev, "failed to enable spi_clk (%d)\n", ret); return ret; -- 2.7.4