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| author | Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> | 2021-11-18 03:10:40 +0000 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2021-11-18 13:57:54 +0000 |
| commit | aadbff4af5c90919cbe67e2c4d77c68cdefa454e (patch) | |
| tree | 13c68fa93c5372b459e8ed68070af46d2aaaff33 /drivers/spi | |
| parent | 5a8f8542e34b6469cd5c5a3d075fa5977d90775e (diff) | |
| download | linux-aadbff4af5c90919cbe67e2c4d77c68cdefa454e.tar.gz linux-aadbff4af5c90919cbe67e2c4d77c68cdefa454e.tar.bz2 linux-aadbff4af5c90919cbe67e2c4d77c68cdefa454e.zip | |
spi: spi-rspi: Add support to deassert/assert reset line
On RZ/G2L SoC we need to explicitly deassert the reset line
for the device to work, use this opportunity to deassert/assert
reset line in spi-rspi driver.
This patch adds support to read the "resets" property (if available)
from DT and perform deassert/assert when required.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20211118031041.2312-3-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-rspi.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c index 41761f0d892a..b7df49a57e5f 100644 --- a/drivers/spi/spi-rspi.c +++ b/drivers/spi/spi-rspi.c @@ -21,6 +21,7 @@ #include <linux/dma-mapping.h> #include <linux/of_device.h> #include <linux/pm_runtime.h> +#include <linux/reset.h> #include <linux/sh_dma.h> #include <linux/spi/spi.h> #include <linux/spi/rspi.h> @@ -1225,8 +1226,14 @@ static const struct of_device_id rspi_of_match[] = { MODULE_DEVICE_TABLE(of, rspi_of_match); +static void rspi_reset_control_assert(void *data) +{ + reset_control_assert(data); +} + static int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr) { + struct reset_control *rstc; u32 num_cs; int error; @@ -1238,6 +1245,24 @@ static int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr) } ctlr->num_chipselect = num_cs; + + rstc = devm_reset_control_get_optional_exclusive(dev, NULL); + if (IS_ERR(rstc)) + return dev_err_probe(dev, PTR_ERR(rstc), + "failed to get reset ctrl\n"); + + error = reset_control_deassert(rstc); + if (error) { + dev_err(dev, "failed to deassert reset %d\n", error); + return error; + } + + error = devm_add_action_or_reset(dev, rspi_reset_control_assert, rstc); + if (error) { + dev_err(dev, "failed to register assert devm action, %d\n", error); + return error; + } + return 0; } #else |