Messages in this thread Patch in this message | | | From | Quentin Schulz <> | Subject | [PATCH 2/2] spi: atmel: add deepest PM support to SAMA5D2 | Date | Fri, 14 Apr 2017 10:22:43 +0200 |
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This adds deepest (Backup+Self-Refresh) PM support to the ATMEL SAMA5D2 SoC's SPI controller.
When resuming from deepest state, it is required to restore MR register as the registers are lost since VDD core has been shut down when entering deepest state on the SAMA5D2.
Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com> ---
v2: - fix commit log explanation on why restoring the registers is required after resuming from deepest state,
drivers/spi/spi-atmel.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index 247d920..1eb83c9 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -1702,8 +1702,17 @@ static int atmel_spi_suspend(struct device *dev) static int atmel_spi_resume(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); + struct atmel_spi *as = spi_master_get_devdata(master); int ret; + ret = clk_prepare_enable(as->clk); + if (ret) + return ret; + + atmel_spi_init(as); + + clk_disable_unprepare(as->clk); + if (!pm_runtime_suspended(dev)) { ret = atmel_spi_runtime_resume(dev); if (ret) -- 2.9.3
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