[PATCH v2 1/2] spi: orion: enable clocks before spi_setup

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From: Marcin Wojtas <mw@xxxxxxxxxxxx>

The spi-orion driver disables its clocks whenever it is not used.
In usual case during boot (i.e. using SPI flash) it is not a problem,
as the child device driver is present and probed along with
spi_register_master() execution.

However in case the child device driver is not ready
(e.g. when its type is module_spi_driver) the spi_setup() callback
can be called after the spi-orion probe. It may happen,
that as a result there will be an attempt to access controller's
registers with the clocks disabled.

Prevent such situations and make sure the clocks are on,
each time the spi_setup() is called.

Signed-off-by: Marcin Wojtas <mw@xxxxxxxxxxxx>
Signed-off-by: Konstantin Porotchkin <kostap@xxxxxxxxxxx>
---
 drivers/spi/spi-orion.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/spi/spi-orion.c b/drivers/spi/spi-orion.c
index b57b8b3cc26e..3bfda4225d45 100644
--- a/drivers/spi/spi-orion.c
+++ b/drivers/spi/spi-orion.c
@@ -507,6 +507,16 @@ static int orion_spi_transfer_one(struct spi_master *master,
 
 static int orion_spi_setup(struct spi_device *spi)
 {
+	struct orion_spi *orion_spi = spi_master_get_devdata(spi->master);
+
+	/*
+	 * Make sure the clocks are enabled before
+	 * configuring the SPI controller.
+	 */
+	clk_prepare_enable(orion_spi->clk);
+	if (!IS_ERR(orion_spi->axi_clk))
+		clk_prepare_enable(orion_spi->axi_clk);
+
 	return orion_spi_setup_transfer(spi, NULL);
 }
 
-- 
2.17.1




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