[PATCH 1/6] spi/s3c64xx: Flush FIFOs prior to cleaning up transfer

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* [PATCH 1/6] spi/s3c64xx: Flush FIFOs prior to cleaning up transfer
@ 2013-09-27 19:44 Mark Brown
  2013-09-27 19:44 ` [PATCH 2/6] spi/s3c64xx: Check that clock enables succeed on runtime resume Mark Brown
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: Mark Brown @ 2013-09-27 19:44 UTC (permalink / raw)
  To: Kukjin Kim
  Cc: linux-samsung-soc, linux-spi, linaro-kernel,
	Łukasz Czerwiński, Mark Brown

From: Mark Brown <broonie@linaro.org>

Ensure that the FIFOs are fully drained before we deassert /CS or do any
delays that have been requested in order to ensure that the behaviour
visible on the bus matches that which was requested by the caller.

Signed-off-by: Mark Brown <broonie@linaro.org>
---
 drivers/spi/spi-s3c64xx.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 229c6b9..2e267ce 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -960,6 +960,8 @@ static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
 			goto out;
 		}
 
+		flush_fifo(sdd);
+
 		if (xfer->delay_usecs)
 			udelay(xfer->delay_usecs);
 
@@ -972,8 +974,6 @@ static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
 		}
 
 		msg->actual_length += xfer->len;
-
-		flush_fifo(sdd);
 	}
 
 out:
-- 
1.8.4.rc3

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH 2/6] spi/s3c64xx: Check that clock enables succeed on runtime resume
  2013-09-27 19:44 [PATCH 1/6] spi/s3c64xx: Flush FIFOs prior to cleaning up transfer Mark Brown
@ 2013-09-27 19:44 ` Mark Brown
  2013-09-27 19:44 ` [PATCH 3/6] spi/s3c64xx: Remove unused gpios field from driver data Mark Brown
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Mark Brown @ 2013-09-27 19:44 UTC (permalink / raw)
  To: Kukjin Kim
  Cc: linux-samsung-soc, linux-spi, linaro-kernel,
	Łukasz Czerwiński, Mark Brown

From: Mark Brown <broonie@linaro.org>

Signed-off-by: Mark Brown <broonie@linaro.org>
---
 drivers/spi/spi-s3c64xx.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 2e267ce..dd5ed13 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -1524,9 +1524,17 @@ static int s3c64xx_spi_runtime_resume(struct device *dev)
 {
 	struct spi_master *master = dev_get_drvdata(dev);
 	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+	int ret;
 
-	clk_prepare_enable(sdd->src_clk);
-	clk_prepare_enable(sdd->clk);
+	ret = clk_prepare_enable(sdd->src_clk);
+	if (ret != 0)
+		return ret;
+
+	ret = clk_prepare_enable(sdd->clk);
+	if (ret != 0) {
+		clk_disable_unprepare(sdd->src_clk);
+		return ret;
+	}
 
 	return 0;
 }
-- 
1.8.4.rc3

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH 3/6] spi/s3c64xx: Remove unused gpios field from driver data
  2013-09-27 19:44 [PATCH 1/6] spi/s3c64xx: Flush FIFOs prior to cleaning up transfer Mark Brown
  2013-09-27 19:44 ` [PATCH 2/6] spi/s3c64xx: Check that clock enables succeed on runtime resume Mark Brown
@ 2013-09-27 19:44 ` Mark Brown
  2013-09-27 19:44 ` [PATCH 4/6] spi/s3c64xx: Use core cs_gpio field Mark Brown
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Mark Brown @ 2013-09-27 19:44 UTC (permalink / raw)
  To: Kukjin Kim
  Cc: linux-samsung-soc, linux-spi, linaro-kernel,
	Łukasz Czerwiński, Mark Brown

From: Mark Brown <broonie@linaro.org>

Signed-off-by: Mark Brown <broonie@linaro.org>
---
 drivers/spi/spi-s3c64xx.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index dd5ed13..7f960db 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -205,7 +205,6 @@ struct s3c64xx_spi_driver_data {
 #endif
 	struct s3c64xx_spi_port_config	*port_conf;
 	unsigned int			port_id;
-	unsigned long			gpios[4];
 	bool				cs_gpio;
 };
 
-- 
1.8.4.rc3

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH 4/6] spi/s3c64xx: Use core cs_gpio field
  2013-09-27 19:44 [PATCH 1/6] spi/s3c64xx: Flush FIFOs prior to cleaning up transfer Mark Brown
  2013-09-27 19:44 ` [PATCH 2/6] spi/s3c64xx: Check that clock enables succeed on runtime resume Mark Brown
  2013-09-27 19:44 ` [PATCH 3/6] spi/s3c64xx: Remove unused gpios field from driver data Mark Brown
@ 2013-09-27 19:44 ` Mark Brown
  2013-09-27 19:44 ` [PATCH 5/6] spi/s3c64xx: Factor transfer start out of enable/disable_cs() Mark Brown
  2013-09-27 19:44 ` [PATCH 6/6] spi/s3c64xx: Enable GPIO /CS prior to starting hardware Mark Brown
  4 siblings, 0 replies; 6+ messages in thread
From: Mark Brown @ 2013-09-27 19:44 UTC (permalink / raw)
  To: Kukjin Kim
  Cc: linux-samsung-soc, linux-spi, linaro-kernel,
	Łukasz Czerwiński, Mark Brown

From: Mark Brown <broonie@linaro.org>

Rather than using the driver custom platform data to store the chip select
GPIO use the cs_gpio field provided by the SPI core, supporting future
refectoring.

Signed-off-by: Mark Brown <broonie@linaro.org>
---
 drivers/spi/spi-s3c64xx.c | 24 ++++++++++--------------
 1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 7f960db..43caeee 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -558,22 +558,18 @@ static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
 static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd,
 						struct spi_device *spi)
 {
-	struct s3c64xx_spi_csinfo *cs;
-
 	if (sdd->tgl_spi != NULL) { /* If last device toggled after mssg */
 		if (sdd->tgl_spi != spi) { /* if last mssg on diff device */
 			/* Deselect the last toggled device */
-			cs = sdd->tgl_spi->controller_data;
-			if (sdd->cs_gpio)
-				gpio_set_value(cs->line,
+			if (spi->cs_gpio >= 0)
+				gpio_set_value(spi->cs_gpio,
 					spi->mode & SPI_CS_HIGH ? 0 : 1);
 		}
 		sdd->tgl_spi = NULL;
 	}
 
-	cs = spi->controller_data;
-	if (sdd->cs_gpio)
-		gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 1 : 0);
+	if (spi->cs_gpio >= 0)
+		gpio_set_value(spi->cs_gpio, spi->mode & SPI_CS_HIGH ? 1 : 0);
 
 	/* Start the signals */
 	writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
@@ -701,13 +697,11 @@ static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
 static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd,
 						struct spi_device *spi)
 {
-	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
-
 	if (sdd->tgl_spi == spi)
 		sdd->tgl_spi = NULL;
 
-	if (sdd->cs_gpio)
-		gpio_set_value(cs->line, spi->mode & SPI_CS_HIGH ? 0 : 1);
+	if (spi->cs_gpio >= 0)
+		gpio_set_value(spi->cs_gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
 
 	/* Quiese the signals */
 	writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
@@ -1070,6 +1064,8 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
 					cs->line, err);
 				goto err_gpio_req;
 			}
+
+			spi->cs_gpio = cs->line;
 		}
 
 		spi_set_ctldata(spi, cs);
@@ -1139,8 +1135,8 @@ static void s3c64xx_spi_cleanup(struct spi_device *spi)
 	struct s3c64xx_spi_driver_data *sdd;
 
 	sdd = spi_master_get_devdata(spi->master);
-	if (cs && sdd->cs_gpio) {
-		gpio_free(cs->line);
+	if (spi->cs_gpio) {
+		gpio_free(spi->cs_gpio);
 		if (spi->dev.of_node)
 			kfree(cs);
 	}
-- 
1.8.4.rc3

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH 5/6] spi/s3c64xx: Factor transfer start out of enable/disable_cs()
  2013-09-27 19:44 [PATCH 1/6] spi/s3c64xx: Flush FIFOs prior to cleaning up transfer Mark Brown
                   ` (2 preceding siblings ...)
  2013-09-27 19:44 ` [PATCH 4/6] spi/s3c64xx: Use core cs_gpio field Mark Brown
@ 2013-09-27 19:44 ` Mark Brown
  2013-09-27 19:44 ` [PATCH 6/6] spi/s3c64xx: Enable GPIO /CS prior to starting hardware Mark Brown
  4 siblings, 0 replies; 6+ messages in thread
From: Mark Brown @ 2013-09-27 19:44 UTC (permalink / raw)
  To: Kukjin Kim
  Cc: linux-samsung-soc, linux-spi, linaro-kernel,
	Łukasz Czerwiński, Mark Brown

From: Mark Brown <broonie@linaro.org>

The hardware level /CS handling is tied to the start of the data path so
is rolled into the same function as we use to manipulate GPIO /CS. In
order to support factoring out the /CS handling into the core separate the
two and explicitly start transfers separately to the /CS handling.

Signed-off-by: Mark Brown <broonie@linaro.org>
---
 drivers/spi/spi-s3c64xx.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 43caeee..2ab96fb 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -570,9 +570,6 @@ static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd,
 
 	if (spi->cs_gpio >= 0)
 		gpio_set_value(spi->cs_gpio, spi->mode & SPI_CS_HIGH ? 1 : 0);
-
-	/* Start the signals */
-	writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 }
 
 static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
@@ -702,9 +699,6 @@ static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd,
 
 	if (spi->cs_gpio >= 0)
 		gpio_set_value(spi->cs_gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
-
-	/* Quiese the signals */
-	writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 }
 
 static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
@@ -930,6 +924,9 @@ static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
 		/* Slave Select */
 		enable_cs(sdd, spi);
 
+		/* Start the signals */
+		writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+
 		spin_unlock_irqrestore(&sdd->lock, flags);
 
 		status = wait_for_xfer(sdd, xfer, use_dma);
@@ -970,10 +967,14 @@ static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
 	}
 
 out:
-	if (!cs_toggle || status)
+	if (!cs_toggle || status) {
+		/* Quiese the signals */
+		writel(S3C64XX_SPI_SLAVE_SIG_INACT,
+		       sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 		disable_cs(sdd, spi);
-	else
+	} else {
 		sdd->tgl_spi = spi;
+	}
 
 	s3c64xx_spi_unmap_mssg(sdd, msg);
 
@@ -1112,11 +1113,13 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
 	}
 
 	pm_runtime_put(&sdd->pdev->dev);
+	writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 	disable_cs(sdd, spi);
 	return 0;
 
 setup_exit:
 	/* setup() returns with device de-selected */
+	writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 	disable_cs(sdd, spi);
 
 	gpio_free(cs->line);
-- 
1.8.4.rc3

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH 6/6] spi/s3c64xx: Enable GPIO /CS prior to starting hardware
  2013-09-27 19:44 [PATCH 1/6] spi/s3c64xx: Flush FIFOs prior to cleaning up transfer Mark Brown
                   ` (3 preceding siblings ...)
  2013-09-27 19:44 ` [PATCH 5/6] spi/s3c64xx: Factor transfer start out of enable/disable_cs() Mark Brown
@ 2013-09-27 19:44 ` Mark Brown
  4 siblings, 0 replies; 6+ messages in thread
From: Mark Brown @ 2013-09-27 19:44 UTC (permalink / raw)
  To: Kukjin Kim
  Cc: linux-samsung-soc, linux-spi, linaro-kernel,
	Łukasz Czerwiński, Mark Brown

From: Mark Brown <broonie@linaro.org>

To help with bisection of future refactoring to share more of the code for
handling a spi_message pull the enabling of GPIO based /CS prior to all
the hardware setup for starting a transfer.

Signed-off-by: Mark Brown <broonie@linaro.org>
---
 drivers/spi/spi-s3c64xx.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 2ab96fb..e631232 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -906,6 +906,9 @@ static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
 			s3c64xx_spi_config(sdd);
 		}
 
+		/* Slave Select */
+		enable_cs(sdd, spi);
+
 		/* Polling method for xfers not bigger than FIFO capacity */
 		use_dma = 0;
 		if (!is_polling(sdd) &&
@@ -921,9 +924,6 @@ static int s3c64xx_spi_transfer_one_message(struct spi_master *master,
 
 		enable_datapath(sdd, spi, xfer, use_dma);
 
-		/* Slave Select */
-		enable_cs(sdd, spi);
-
 		/* Start the signals */
 		writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 
-- 
1.8.4.rc3

^ permalink raw reply related	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2013-09-27 19:45 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-09-27 19:44 [PATCH 1/6] spi/s3c64xx: Flush FIFOs prior to cleaning up transfer Mark Brown
2013-09-27 19:44 ` [PATCH 2/6] spi/s3c64xx: Check that clock enables succeed on runtime resume Mark Brown
2013-09-27 19:44 ` [PATCH 3/6] spi/s3c64xx: Remove unused gpios field from driver data Mark Brown
2013-09-27 19:44 ` [PATCH 4/6] spi/s3c64xx: Use core cs_gpio field Mark Brown
2013-09-27 19:44 ` [PATCH 5/6] spi/s3c64xx: Factor transfer start out of enable/disable_cs() Mark Brown
2013-09-27 19:44 ` [PATCH 6/6] spi/s3c64xx: Enable GPIO /CS prior to starting hardware Mark Brown

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