diff options
| author | Andy Chiu <andy.chiu@sifive.com> | 2022-06-10 10:44:59 +0300 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2022-06-10 15:32:24 +0300 |
| commit | a1f0161eadbd7941c09b5f4c6a210c390d2b86d6 (patch) | |
| tree | 338da232914da9820c2365e443cc6f9f70a23146 /drivers/spi/spi-sifive.c | |
| parent | 0356163e5883e298b518cd16517be633824987f9 (diff) | |
| download | linux-a1f0161eadbd7941c09b5f4c6a210c390d2b86d6.tar.xz | |
spi: sifive: add PM callbacks to support suspend/resume
The patch has been tested on Unmatched using pm_test. The Unmatched board
uses SD over SPI and it was tested by initiating S2RAM cycles for all
devices while reading/writing files at the same time. We found no dropped
connection to the card or corrupted filesystem during test cycles.
Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Reviewed-by: Greentime Hu <greentime.hu@sifive.com>
Link: https://lore.kernel.org/r/20220610074459.3261383-2-andy.chiu@sifive.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-sifive.c')
| -rw-r--r-- | drivers/spi/spi-sifive.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/drivers/spi/spi-sifive.c b/drivers/spi/spi-sifive.c index f7c1e20432e0..e29e85cee88a 100644 --- a/drivers/spi/spi-sifive.c +++ b/drivers/spi/spi-sifive.c @@ -427,6 +427,44 @@ static int sifive_spi_remove(struct platform_device *pdev) return 0; } +static int sifive_spi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct sifive_spi *spi = spi_master_get_devdata(master); + int ret; + + ret = spi_master_suspend(master); + if (ret) + return ret; + + /* Disable all the interrupts just in case */ + sifive_spi_write(spi, SIFIVE_SPI_REG_IE, 0); + + clk_disable_unprepare(spi->clk); + + return ret; +} + +static int sifive_spi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct sifive_spi *spi = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(spi->clk); + if (ret) + return ret; + ret = spi_master_resume(master); + if (ret) + clk_disable_unprepare(spi->clk); + + return ret; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(sifive_spi_pm_ops, + sifive_spi_suspend, sifive_spi_resume); + + static const struct of_device_id sifive_spi_of_match[] = { { .compatible = "sifive,spi0", }, {} @@ -438,6 +476,7 @@ static struct platform_driver sifive_spi_driver = { .remove = sifive_spi_remove, .driver = { .name = SIFIVE_SPI_DRIVER_NAME, + .pm = &sifive_spi_pm_ops, .of_match_table = sifive_spi_of_match, }, }; |