[PATCH v3 1/6] spi: sun6i: coding style/readability improvements
Sergey Suloev
ssuloev at orpaltech.com
Tue Apr 3 08:44:44 PDT 2018
Minor changes to fulfill the coding style and improve
the readability of the code.
Changes in v2:
1) Fixed issue with misplacing a piece of code that requires access
to the transfer structure into sun6i_spi_prepare_message() function
where the transfer structure is not available.
Signed-off-by: Sergey Suloev <ssuloev at orpaltech.com>
---
drivers/spi/spi-sun6i.c | 97 +++++++++++++++++++++++++++++--------------------
1 file changed, 58 insertions(+), 39 deletions(-)
diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c
index 8533f4e..88ad45e 100644
--- a/drivers/spi/spi-sun6i.c
+++ b/drivers/spi/spi-sun6i.c
@@ -88,8 +88,12 @@
#define SUN6I_TXDATA_REG 0x200
#define SUN6I_RXDATA_REG 0x300
+#define SUN6I_SPI_MODE_BITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST)
+
+#define SUN6I_SPI_MAX_SPEED_HZ 100000000
+#define SUN6I_SPI_MIN_SPEED_HZ 3000
+
struct sun6i_spi {
- struct spi_master *master;
void __iomem *base_addr;
struct clk *hclk;
struct clk *mclk;
@@ -189,6 +193,9 @@ static void sun6i_spi_set_cs(struct spi_device *spi, bool enable)
else
reg &= ~SUN6I_TFR_CTL_CS_LEVEL;
+ /* We want to control the chip select manually */
+ reg |= SUN6I_TFR_CTL_CS_MANUAL;
+
sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg);
}
@@ -197,6 +204,39 @@ static size_t sun6i_spi_max_transfer_size(struct spi_device *spi)
return SUN6I_MAX_XFER_SIZE - 1;
}
+static int sun6i_spi_prepare_message(struct spi_master *master,
+ struct spi_message *msg)
+{
+ struct spi_device *spi = msg->spi;
+ struct sun6i_spi *sspi = spi_master_get_devdata(master);
+ u32 reg;
+
+ /*
+ * Setup the transfer control register: Chip Select,
+ * polarities, etc.
+ */
+ reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG);
+
+ if (spi->mode & SPI_CPOL)
+ reg |= SUN6I_TFR_CTL_CPOL;
+ else
+ reg &= ~SUN6I_TFR_CTL_CPOL;
+
+ if (spi->mode & SPI_CPHA)
+ reg |= SUN6I_TFR_CTL_CPHA;
+ else
+ reg &= ~SUN6I_TFR_CTL_CPHA;
+
+ if (spi->mode & SPI_LSB_FIRST)
+ reg |= SUN6I_TFR_CTL_FBS;
+ else
+ reg &= ~SUN6I_TFR_CTL_FBS;
+
+ sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg);
+
+ return 0;
+}
+
static int sun6i_spi_transfer_one(struct spi_master *master,
struct spi_device *spi,
struct spi_transfer *tfr)
@@ -235,27 +275,8 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
(trig_level << SUN6I_FIFO_CTL_RF_RDY_TRIG_LEVEL_BITS) |
(trig_level << SUN6I_FIFO_CTL_TF_ERQ_TRIG_LEVEL_BITS));
- /*
- * Setup the transfer control register: Chip Select,
- * polarities, etc.
- */
- reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG);
-
- if (spi->mode & SPI_CPOL)
- reg |= SUN6I_TFR_CTL_CPOL;
- else
- reg &= ~SUN6I_TFR_CTL_CPOL;
-
- if (spi->mode & SPI_CPHA)
- reg |= SUN6I_TFR_CTL_CPHA;
- else
- reg &= ~SUN6I_TFR_CTL_CPHA;
-
- if (spi->mode & SPI_LSB_FIRST)
- reg |= SUN6I_TFR_CTL_FBS;
- else
- reg &= ~SUN6I_TFR_CTL_FBS;
+ reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG);
/*
* If it's a TX only transfer, we don't want to fill the RX
* FIFO with bogus data
@@ -265,11 +286,9 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
else
reg |= SUN6I_TFR_CTL_DHB;
- /* We want to control the chip select manually */
- reg |= SUN6I_TFR_CTL_CS_MANUAL;
-
sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg);
+
/* Ensure that we have a parent clock fast enough */
mclk_rate = clk_get_rate(sspi->mclk);
if (mclk_rate < (2 * tfr->speed_hz)) {
@@ -442,12 +461,24 @@ static int sun6i_spi_probe(struct platform_device *pdev)
struct resource *res;
int ret = 0, irq;
- master = spi_alloc_master(&pdev->dev, sizeof(struct sun6i_spi));
+ master = spi_alloc_master(&pdev->dev, sizeof(*sspi));
if (!master) {
dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
return -ENOMEM;
}
+ master->max_speed_hz = SUN6I_SPI_MAX_SPEED_HZ;
+ master->min_speed_hz = SUN6I_SPI_MIN_SPEED_HZ;
+ master->num_chipselect = 4;
+ master->mode_bits = SUN6I_SPI_MODE_BITS;
+ master->bits_per_word_mask = SPI_BPW_MASK(8);
+ master->set_cs = sun6i_spi_set_cs;
+ master->prepare_message = sun6i_spi_prepare_message;
+ master->transfer_one = sun6i_spi_transfer_one;
+ master->max_transfer_size = sun6i_spi_max_transfer_size;
+ master->dev.of_node = pdev->dev.of_node;
+ master->auto_runtime_pm = true;
+
platform_set_drvdata(pdev, master);
sspi = spi_master_get_devdata(master);
@@ -466,26 +497,14 @@ static int sun6i_spi_probe(struct platform_device *pdev)
}
ret = devm_request_irq(&pdev->dev, irq, sun6i_spi_handler,
- 0, "sun6i-spi", sspi);
+ 0, dev_name(&pdev->dev), sspi);
if (ret) {
dev_err(&pdev->dev, "Cannot request IRQ\n");
goto err_free_master;
}
- sspi->master = master;
sspi->fifo_depth = (unsigned long)of_device_get_match_data(&pdev->dev);
- master->max_speed_hz = 100 * 1000 * 1000;
- master->min_speed_hz = 3 * 1000;
- master->set_cs = sun6i_spi_set_cs;
- master->transfer_one = sun6i_spi_transfer_one;
- master->num_chipselect = 4;
- master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
- master->bits_per_word_mask = SPI_BPW_MASK(8);
- master->dev.of_node = pdev->dev.of_node;
- master->auto_runtime_pm = true;
- master->max_transfer_size = sun6i_spi_max_transfer_size;
-
sspi->hclk = devm_clk_get(&pdev->dev, "ahb");
if (IS_ERR(sspi->hclk)) {
dev_err(&pdev->dev, "Unable to acquire AHB clock\n");
@@ -525,7 +544,7 @@ static int sun6i_spi_probe(struct platform_device *pdev)
ret = devm_spi_register_master(&pdev->dev, master);
if (ret) {
- dev_err(&pdev->dev, "cannot register SPI master\n");
+ dev_err(&pdev->dev, "Couldn't register SPI master\n");
goto err_pm_disable;
}
--
2.16.2
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