linux-kernel - [PATCH v3 1/3] spi: amd: Use iopoll for busy waiting

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Date:   Wed, 16 Feb 2022 10:16:36 -0300
From:   André Almeida <andrealmeid@...labora.com>
To:     Sanjay R Mehta <sanju.mehta@....com>,
        Mark Brown <broonie@...nel.org>, linux-spi@...r.kernel.org,
        linux-kernel@...r.kernel.org, kernel@...labora.com,
        Stephen Rothwell <sfr@...b.auug.org.au>
Cc:     André Almeida <andrealmeid@...labora.com>
Subject: [PATCH v3 1/3] spi: amd: Use iopoll for busy waiting

Instead of implementing a custom IO busy wait function, just use
readl_poll_timeout().

Signed-off-by: André Almeida <andrealmeid@...labora.com>
---
 drivers/spi/spi-amd.c | 13 ++++---------
 1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/drivers/spi/spi-amd.c b/drivers/spi/spi-amd.c
index 4b3ac7aceaf6..899b8d90ff61 100644
--- a/drivers/spi/spi-amd.c
+++ b/drivers/spi/spi-amd.c
@@ -12,6 +12,7 @@
 #include <linux/platform_device.h>
 #include <linux/delay.h>
 #include <linux/spi/spi.h>
+#include <linux/iopoll.h>
 
 #define AMD_SPI_CTRL0_REG	0x00
 #define AMD_SPI_EXEC_CMD	BIT(16)
@@ -103,16 +104,10 @@ static inline void amd_spi_set_tx_count(struct amd_spi *amd_spi, u8 tx_count)
 
 static int amd_spi_busy_wait(struct amd_spi *amd_spi)
 {
-	int timeout = 100000;
+	u32 val;
 
-	/* poll for SPI bus to become idle */
-	while (amd_spi_readreg32(amd_spi, AMD_SPI_CTRL0_REG) & AMD_SPI_BUSY) {
-		usleep_range(10, 20);
-		if (timeout-- < 0)
-			return -ETIMEDOUT;
-	}
-
-	return 0;
+	return readl_poll_timeout(amd_spi->io_remap_addr + AMD_SPI_CTRL0_REG,
+				  val, !(val & AMD_SPI_BUSY), 20, 2000000);
 }
 
 static int amd_spi_execute_opcode(struct amd_spi *amd_spi)
-- 
2.35.1