[PATCHv3 0/3] spi: omap2-mcspi: driver updates

[PATCHv3 0/3] spi: omap2-mcspi: driver updates

[Shubhrajyoti D]

The patch series does the following cleanups
- Makes the driver use autosuspend
- Folds Benoit's bus_num removal patch in the series
- The tmp variable is used to write this can be optimised 
 as it is not needed if the value is directly written.
 Acknowledge  Tarun for the suggestion.

This is also available through
git     : git://gitorious.org/linus-tree/linus-tree.git
branch  : spi_next

Rebased to Grant's spi/next branch.

 

Benoit Cousson (1):
  spi/omap: Remove bus_num usage for instance index

Shubhrajyoti D (2):
  spi: omap2-mcspi: add support for pm_runtime autosuspend
  spi: omap2-mcspi: Trivial optimisation

 drivers/spi/spi-omap2-mcspi.c |   86 +++++++++++++++++++---------------------
 1 files changed, 41 insertions(+), 45 deletions(-)

[PATCHv3 1/3] spi/omap: Remove bus_num usage for instance index

[Shubhrajyoti D]

From: Benoit Cousson <b-cousson@ti.com>

bus_num was used to reference the mcspi controller instance in a fixed array.
Remove this array and store this information directly inside drvdata structure.

bus_num is now just set if the pdev->id is present or with -1 for dynamic
allocation by SPI core, but the driver does not access it anymore.

Clean some bad comments format, and remove un-needed space.

Signed-off-by: Benoit Cousson <b-cousson@ti.com>
[Cleanup the OMAP2_MCSPI_MAX_CTRL macro as it is not needed anymore]
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/spi/spi-omap2-mcspi.c |   75 ++++++++++++++++++----------------------
 1 files changed, 34 insertions(+), 41 deletions(-)

diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c
index 33f54cd..1907ed2 100644
--- a/drivers/spi/spi-omap2-mcspi.c
+++ b/drivers/spi/spi-omap2-mcspi.c
@@ -45,9 +45,6 @@
 
 #define OMAP2_MCSPI_MAX_FREQ		48000000
 
-/* OMAP2 has 3 SPI controllers, while OMAP3 has 4 */
-#define OMAP2_MCSPI_MAX_CTRL 		4
-
 #define OMAP2_MCSPI_REVISION		0x00
 #define OMAP2_MCSPI_SYSSTATUS		0x14
 #define OMAP2_MCSPI_IRQSTATUS		0x18
@@ -111,6 +108,16 @@ struct omap2_mcspi_dma {
 #define DMA_MIN_BYTES			160
 
 
+/*
+ * Used for context save and restore, structure members to be updated whenever
+ * corresponding registers are modified.
+ */
+struct omap2_mcspi_regs {
+	u32 modulctrl;
+	u32 wakeupenable;
+	struct list_head cs;
+};
+
 struct omap2_mcspi {
 	struct work_struct	work;
 	/* lock protects queue and registers */
@@ -122,8 +129,9 @@ struct omap2_mcspi {
 	unsigned long		phys;
 	/* SPI1 has 4 channels, while SPI2 has 2 */
 	struct omap2_mcspi_dma	*dma_channels;
-	struct  device		*dev;
+	struct device		*dev;
 	struct workqueue_struct *wq;
+	struct omap2_mcspi_regs ctx;
 };
 
 struct omap2_mcspi_cs {
@@ -135,17 +143,6 @@ struct omap2_mcspi_cs {
 	u32			chconf0;
 };
 
-/* used for context save and restore, structure members to be updated whenever
- * corresponding registers are modified.
- */
-struct omap2_mcspi_regs {
-	u32 modulctrl;
-	u32 wakeupenable;
-	struct list_head cs;
-};
-
-static struct omap2_mcspi_regs omap2_mcspi_ctx[OMAP2_MCSPI_MAX_CTRL];
-
 #define MOD_REG_BIT(val, mask, set) do { \
 	if (set) \
 		val |= mask; \
@@ -236,9 +233,12 @@ static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
 
 static void omap2_mcspi_set_master_mode(struct spi_master *master)
 {
+	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
+	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 	u32 l;
 
-	/* setup when switching from (reset default) slave mode
+	/*
+	 * Setup when switching from (reset default) slave mode
 	 * to single-channel master mode
 	 */
 	l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
@@ -247,24 +247,20 @@ static void omap2_mcspi_set_master_mode(struct spi_master *master)
 	MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_SINGLE, 1);
 	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
 
-	omap2_mcspi_ctx[master->bus_num - 1].modulctrl = l;
+	ctx->modulctrl = l;
 }
 
 static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
 {
-	struct spi_master *spi_cntrl;
-	struct omap2_mcspi_cs *cs;
-	spi_cntrl = mcspi->master;
+	struct spi_master	*spi_cntrl = mcspi->master;
+	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
+	struct omap2_mcspi_cs	*cs;
 
 	/* McSPI: context restore */
-	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL,
-			omap2_mcspi_ctx[spi_cntrl->bus_num - 1].modulctrl);
+	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
+	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
 
-	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE,
-			omap2_mcspi_ctx[spi_cntrl->bus_num - 1].wakeupenable);
-
-	list_for_each_entry(cs, &omap2_mcspi_ctx[spi_cntrl->bus_num - 1].cs,
-			node)
+	list_for_each_entry(cs, &ctx->cs, node)
 		__raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
 }
 static void omap2_mcspi_disable_clocks(struct omap2_mcspi *mcspi)
@@ -777,7 +773,8 @@ static int omap2_mcspi_request_dma(struct spi_device *spi)
 static int omap2_mcspi_setup(struct spi_device *spi)
 {
 	int			ret;
-	struct omap2_mcspi	*mcspi;
+	struct omap2_mcspi	*mcspi = spi_master_get_devdata(spi->master);
+	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 	struct omap2_mcspi_dma	*mcspi_dma;
 	struct omap2_mcspi_cs	*cs = spi->controller_state;
 
@@ -787,7 +784,6 @@ static int omap2_mcspi_setup(struct spi_device *spi)
 		return -EINVAL;
 	}
 
-	mcspi = spi_master_get_devdata(spi->master);
 	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
 
 	if (!cs) {
@@ -799,8 +795,7 @@ static int omap2_mcspi_setup(struct spi_device *spi)
 		cs->chconf0 = 0;
 		spi->controller_state = cs;
 		/* Link this to context save list */
-		list_add_tail(&cs->node,
-			&omap2_mcspi_ctx[mcspi->master->bus_num - 1].cs);
+		list_add_tail(&cs->node, &ctx->cs);
 	}
 
 	if (mcspi_dma->dma_rx_channel == -1
@@ -1052,8 +1047,9 @@ static int omap2_mcspi_transfer(struct spi_device *spi, struct spi_message *m)
 static int __init omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
 {
 	struct spi_master	*master = mcspi->master;
+	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
 	u32			tmp;
-	int ret = 0;
+	int			ret = 0;
 
 	ret = omap2_mcspi_enable_clocks(mcspi);
 	if (ret < 0)
@@ -1061,7 +1057,7 @@ static int __init omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
 
 	tmp = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
 	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, tmp);
-	omap2_mcspi_ctx[master->bus_num - 1].wakeupenable = tmp;
+	ctx->wakeupenable = tmp;
 
 	omap2_mcspi_set_master_mode(master);
 	omap2_mcspi_disable_clocks(mcspi);
@@ -1108,7 +1104,6 @@ static int __devinit omap2_mcspi_probe(struct platform_device *pdev)
 	struct omap2_mcspi	*mcspi;
 	struct resource		*r;
 	int			status = 0, i;
-	char			wq_name[20];
 	u32			regs_offset = 0;
 	static int		bus_num = 1;
 	struct device_node	*node = pdev->dev.of_node;
@@ -1149,8 +1144,7 @@ static int __devinit omap2_mcspi_probe(struct platform_device *pdev)
 	mcspi = spi_master_get_devdata(master);
 	mcspi->master = master;
 
-	sprintf(wq_name, "omap2_mcspi/%d", master->bus_num);
-	mcspi->wq = alloc_workqueue(wq_name, WQ_MEM_RECLAIM, 1);
+	mcspi->wq = alloc_workqueue(dev_name(&pdev->dev), WQ_MEM_RECLAIM, 1);
 	if (mcspi->wq == NULL) {
 		status = -ENOMEM;
 		goto free_master;
@@ -1178,7 +1172,7 @@ static int __devinit omap2_mcspi_probe(struct platform_device *pdev)
 
 	spin_lock_init(&mcspi->lock);
 	INIT_LIST_HEAD(&mcspi->msg_queue);
-	INIT_LIST_HEAD(&omap2_mcspi_ctx[master->bus_num - 1].cs);
+	INIT_LIST_HEAD(&mcspi->ctx.cs);
 
 	mcspi->dma_channels = kcalloc(master->num_chipselect,
 			sizeof(struct omap2_mcspi_dma),
@@ -1275,13 +1269,12 @@ static int omap2_mcspi_resume(struct device *dev)
 {
 	struct spi_master	*master = dev_get_drvdata(dev);
 	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
-	struct omap2_mcspi_cs *cs;
+	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
+	struct omap2_mcspi_cs	*cs;
 
 	omap2_mcspi_enable_clocks(mcspi);
-	list_for_each_entry(cs, &omap2_mcspi_ctx[master->bus_num - 1].cs,
-			    node) {
+	list_for_each_entry(cs, &ctx->cs, node) {
 		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
-
 			/*
 			 * We need to toggle CS state for OMAP take this
 			 * change in account.
-- 
1.7.1

[PATCHv3 2/3] spi: omap2-mcspi: add support for pm_runtime autosuspend

[Shubhrajyoti D]

Adds support for configuring the omap2-mcspi driver use autosuspend for
runtime power management. This can reduce the latency in starting an
spi transfer by not suspending the device immediately following
completion of a transfer. If another transfer then takes place before
the autosuspend timeout (2 secs), the call to resume the device can
return immediately saving some save/ restore cycles.

Acked-by: Govindraj.R <govindraj.raja@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/spi/spi-omap2-mcspi.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)

diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c
index 1907ed2..0b0da2f 100644
--- a/drivers/spi/spi-omap2-mcspi.c
+++ b/drivers/spi/spi-omap2-mcspi.c
@@ -44,6 +44,7 @@
 #include <plat/mcspi.h>
 
 #define OMAP2_MCSPI_MAX_FREQ		48000000
+#define SPI_AUTOSUSPEND_TIMEOUT		2000
 
 #define OMAP2_MCSPI_REVISION		0x00
 #define OMAP2_MCSPI_SYSSTATUS		0x14
@@ -265,7 +266,8 @@ static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
 }
 static void omap2_mcspi_disable_clocks(struct omap2_mcspi *mcspi)
 {
-	pm_runtime_put_sync(mcspi->dev);
+	pm_runtime_mark_last_busy(mcspi->dev);
+	pm_runtime_put_autosuspend(mcspi->dev);
 }
 
 static int omap2_mcspi_enable_clocks(struct omap2_mcspi *mcspi)
@@ -1212,6 +1214,8 @@ static int __devinit omap2_mcspi_probe(struct platform_device *pdev)
 	if (status < 0)
 		goto dma_chnl_free;
 
+	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
 	pm_runtime_enable(&pdev->dev);
 
 	if (status || omap2_mcspi_master_setup(mcspi) < 0)
-- 
1.7.1

[PATCHv3 3/3] spi: omap2-mcspi: Trivial optimisation

[Shubhrajyoti D]

Trivial optimisation of tmp variable by directly writing the value
to the register.

Cc :  Tarun Kanti DebBarma <tarun.kanti@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/spi/spi-omap2-mcspi.c |    7 +++----
 1 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c
index 0b0da2f..f374eee 100644
--- a/drivers/spi/spi-omap2-mcspi.c
+++ b/drivers/spi/spi-omap2-mcspi.c
@@ -1050,16 +1050,15 @@ static int __init omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
 {
 	struct spi_master	*master = mcspi->master;
 	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
-	u32			tmp;
 	int			ret = 0;
 
 	ret = omap2_mcspi_enable_clocks(mcspi);
 	if (ret < 0)
 		return ret;
 
-	tmp = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
-	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, tmp);
-	ctx->wakeupenable = tmp;
+	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
+				OMAP2_MCSPI_WAKEUPENABLE_WKEN);
+	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
 
 	omap2_mcspi_set_master_mode(master);
 	omap2_mcspi_disable_clocks(mcspi);
-- 
1.7.1

Re: [PATCHv3 0/3] spi: omap2-mcspi: driver updates

[Grant Likely]

On Sat, 31 Mar 2012 17:06:55 +0530, Shubhrajyoti D <shubhrajyoti@ti.com> wrote:
> The patch series does the following cleanups
> - Makes the driver use autosuspend
> - Folds Benoit's bus_num removal patch in the series
> - The tmp variable is used to write this can be optimised 
>  as it is not needed if the value is directly written.
>  Acknowledge  Tarun for the suggestion.
> 
> This is also available through
> git     : git://gitorious.org/linus-tree/linus-tree.git
> branch  : spi_next
> 
> Rebased to Grant's spi/next branch.

Merged, thanks.

BTW, it's easier to pull if you put the branch after the git URL (I
can cut and paste all at once):

	git://gitorious.org/linus-tree/linus-tree.git spi_next

"git request-pull" can be your friend here.

I've also respun the top commit (Trivial optimization...) because the
Cc tag format was wrong in the commit text (whitespace errors).
You'll need to be pendantic about stuff like that for trees that I
might pull.

g.


> 
>  
> 
> Benoit Cousson (1):
>   spi/omap: Remove bus_num usage for instance index
> 
> Shubhrajyoti D (2):
>   spi: omap2-mcspi: add support for pm_runtime autosuspend
>   spi: omap2-mcspi: Trivial optimisation
> 
>  drivers/spi/spi-omap2-mcspi.c |   86 +++++++++++++++++++---------------------
>  1 files changed, 41 insertions(+), 45 deletions(-)
> 
> 
> ------------------------------------------------------------------------------
> This SF email is sponsosred by:
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-- 
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies,Ltd.

Re: [PATCHv3 0/3] spi: omap2-mcspi: driver updates

[Shubhrajyoti Datta]

Hi Grant

On Tue, Apr 3, 2012 at 1:10 AM, Grant Likely <grant.likely@secretlab.ca> wrote:
> On Sat, 31 Mar 2012 17:06:55 +0530, Shubhrajyoti D <shubhrajyoti@ti.com> wrote:
>> The patch series does the following cleanups
>> - Makes the driver use autosuspend
>> - Folds Benoit's bus_num removal patch in the series
>> - The tmp variable is used to write this can be optimised
>>  as it is not needed if the value is directly written.
>>  Acknowledge  Tarun for the suggestion.
>>
>> This is also available through
>> git     : git://gitorious.org/linus-tree/linus-tree.git
>> branch  : spi_next
>>
>> Rebased to Grant's spi/next branch.
>
> Merged, thanks.
Thanks ,

>
> BTW, it's easier to pull if you put the branch after the git URL (I
> can cut and paste all at once):
>
>        git://gitorious.org/linus-tree/linus-tree.git spi_next
>
> "git request-pull" can be your friend here.
>
OK good idea will do that.