From: Sascha Hauer <s.hauer@pengutronix.de>
To: "open list:BAREBOX" <barebox@lists.infradead.org>
Subject: [PATCH v2 4/5] spi: spi-gpio: deassert CS during setup
Date: Thu, 26 Sep 2024 13:21:40 +0200 [thread overview]
Message-ID: <20240926-spi-gpio-v2-4-3bf7b511c8c0@pengutronix.de> (raw)
In-Reply-To: <20240926-spi-gpio-v2-0-3bf7b511c8c0@pengutronix.de>
The initial CS gpio state is unknown. When it's asserted the first
transfer might fail. Deassert the CS during setup to make sure the
slave gets a fresh start.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
drivers/spi/gpio_spi.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/spi/gpio_spi.c b/drivers/spi/gpio_spi.c
index 417e8db30e..36e6204283 100644
--- a/drivers/spi/gpio_spi.c
+++ b/drivers/spi/gpio_spi.c
@@ -165,6 +165,7 @@ static int gpio_spi_transfer(struct spi_device *spi, struct spi_message *msg)
static int gpio_spi_setup(struct spi_device *spi)
{
+ gpio_spi_set_cs(spi, 0);
return 0;
}
--
2.39.5
next prev parent reply other threads:[~2024-09-26 11:23 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-09-26 11:21 [PATCH v2 0/5] spi-gpio updates Sascha Hauer
2024-09-26 11:21 ` [PATCH v2 1/5] spi: spi-gpio: actually delay in spidelay() Sascha Hauer
2024-09-26 11:21 ` [PATCH v2 2/5] spi: spi-gpio: support different word widths Sascha Hauer
2024-09-26 11:21 ` [PATCH v2 3/5] spi: spi-gpio: switch to new gpio binding Sascha Hauer
2024-09-26 11:21 ` Sascha Hauer [this message]
2024-09-26 11:21 ` [PATCH v2 5/5] spi: spi-gpio: switch to gpiod api Sascha Hauer
2024-09-27 10:40 ` [PATCH v2 0/5] spi-gpio updates Sascha Hauer
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