* [PATCH 3/3] spi: spi-omap2-mcspi.c: Toggle CS after each word
@ 2013-01-23 18:08 Matthias Brugger
2013-01-24 7:38 ` Jarkko Nikula
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Matthias Brugger @ 2013-01-23 18:08 UTC (permalink / raw)
To: Grant Likely, Mark Brown, Tony Lindgren, Daniel Mack,
Jarkko Nikula, Greg Kroah-Hartman, eballetbo, javier.martinez,
ezequiel.garcia, spi-devel-general, linux-omap
Cc: Matthias Brugger
This patch allows the board code to define SPI devices which needs to
toggle the chip select after every word send. This is needed to get a
better resolution reading e.g. an ADC data stream.
Apart from that, as in the normal code CS is controlled by software,
a transfer is done much faster.
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
---
drivers/spi/spi-omap2-mcspi.c | 34 ++++++++++++++++++++-------
include/linux/platform_data/spi-omap2-mcspi.h | 3 +++
2 files changed, 29 insertions(+), 8 deletions(-)
diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c
index b610f52..12789fc 100644
--- a/drivers/spi/spi-omap2-mcspi.c
+++ b/drivers/spi/spi-omap2-mcspi.c
@@ -927,6 +927,7 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
struct spi_device *spi;
struct spi_transfer *t = NULL;
+ struct spi_master *master;
int cs_active = 0;
struct omap2_mcspi_cs *cs;
struct omap2_mcspi_device_config *cd;
@@ -935,6 +936,7 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
u32 chconf;
spi = m->spi;
+ master = spi->master;
cs = spi->controller_state;
cd = spi->controller_data;
@@ -952,6 +954,14 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
if (!t->speed_hz && !t->bits_per_word)
par_override = 0;
}
+ if (cd && cd->cs_per_word) {
+ chconf = mcspi->ctx.modulctrl;
+ chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
+ mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
+ mcspi->ctx.modulctrl =
+ mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
+ }
+
if (!cs_active) {
omap2_mcspi_force_cs(spi, 1);
@@ -1013,6 +1023,14 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
if (cs_active)
omap2_mcspi_force_cs(spi, 0);
+ if (cd && cd->cs_per_word) {
+ chconf = mcspi->ctx.modulctrl;
+ chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
+ mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
+ mcspi->ctx.modulctrl =
+ mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
+ }
+
omap2_mcspi_set_enable(spi, 0);
m->status = status;
@@ -1020,7 +1038,7 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
}
static int omap2_mcspi_transfer_one_message(struct spi_master *master,
- struct spi_message *m)
+ struct spi_message *m)
{
struct omap2_mcspi *mcspi;
struct spi_transfer *t;
@@ -1041,7 +1059,7 @@ static int omap2_mcspi_transfer_one_message(struct spi_master *master,
|| (len && !(rx_buf || tx_buf))
|| (t->bits_per_word &&
( t->bits_per_word < 4
- || t->bits_per_word > 32))) {
+ || t->bits_per_word > 32))) {
dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
t->speed_hz,
len,
@@ -1052,8 +1070,8 @@ static int omap2_mcspi_transfer_one_message(struct spi_master *master,
}
if (t->speed_hz && t->speed_hz < (OMAP2_MCSPI_MAX_FREQ >> 15)) {
dev_dbg(mcspi->dev, "speed_hz %d below minimum %d Hz\n",
- t->speed_hz,
- OMAP2_MCSPI_MAX_FREQ >> 15);
+ t->speed_hz,
+ OMAP2_MCSPI_MAX_FREQ >> 15);
return -EINVAL;
}
@@ -1099,7 +1117,7 @@ static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
return ret;
mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
- OMAP2_MCSPI_WAKEUPENABLE_WKEN);
+ OMAP2_MCSPI_WAKEUPENABLE_WKEN);
ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
omap2_mcspi_set_master_mode(master);
@@ -1228,7 +1246,7 @@ static int omap2_mcspi_probe(struct platform_device *pdev)
sprintf(dma_ch_name, "rx%d", i);
dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
- dma_ch_name);
+ dma_ch_name);
if (!dma_res) {
dev_dbg(&pdev->dev, "cannot get DMA RX channel\n");
status = -ENODEV;
@@ -1238,7 +1256,7 @@ static int omap2_mcspi_probe(struct platform_device *pdev)
mcspi->dma_channels[i].dma_rx_sync_dev = dma_res->start;
sprintf(dma_ch_name, "tx%d", i);
dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
- dma_ch_name);
+ dma_ch_name);
if (!dma_res) {
dev_dbg(&pdev->dev, "cannot get DMA TX channel\n");
status = -ENODEV;
@@ -1254,7 +1272,7 @@ static int omap2_mcspi_probe(struct platform_device *pdev)
pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
if (IS_ERR(pinctrl))
dev_warn(&pdev->dev,
- "pins are not configured from the driver\n");
+ "pins are not configured from the driver\n");
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
diff --git a/include/linux/platform_data/spi-omap2-mcspi.h b/include/linux/platform_data/spi-omap2-mcspi.h
index a65572d..c100456 100644
--- a/include/linux/platform_data/spi-omap2-mcspi.h
+++ b/include/linux/platform_data/spi-omap2-mcspi.h
@@ -22,6 +22,9 @@ struct omap2_mcspi_dev_attr {
struct omap2_mcspi_device_config {
unsigned turbo_mode:1;
+
+ /* toggle chip select after every word */
+ unsigned cs_per_word:1;
};
#endif
--
1.7.11.7
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 3/3] spi: spi-omap2-mcspi.c: Toggle CS after each word
2013-01-23 18:08 [PATCH 3/3] spi: spi-omap2-mcspi.c: Toggle CS after each word Matthias Brugger
@ 2013-01-24 7:38 ` Jarkko Nikula
2013-01-24 11:06 ` Mark Brown
2013-01-24 22:19 ` Matt Porter
2 siblings, 0 replies; 4+ messages in thread
From: Jarkko Nikula @ 2013-01-24 7:38 UTC (permalink / raw)
To: Matthias Brugger
Cc: Grant Likely, Mark Brown, Tony Lindgren, Daniel Mack,
Greg Kroah-Hartman, eballetbo, javier.martinez, ezequiel.garcia,
spi-devel-general, linux-omap
Hi
On Wed, 23 Jan 2013 19:08:49 +0100
Matthias Brugger <matthias.bgg@gmail.com> wrote:
> @@ -1020,7 +1038,7 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
> }
>
> static int omap2_mcspi_transfer_one_message(struct spi_master *master,
> - struct spi_message *m)
> + struct spi_message *m)
> {
> struct omap2_mcspi *mcspi;
> struct spi_transfer *t;
> @@ -1041,7 +1059,7 @@ static int omap2_mcspi_transfer_one_message(struct spi_master *master,
> || (len && !(rx_buf || tx_buf))
> || (t->bits_per_word &&
> ( t->bits_per_word < 4
> - || t->bits_per_word > 32))) {
> + || t->bits_per_word > 32))) {
> dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
> t->speed_hz,
> len,
Just a sidenote but these indentation changes should go to another patch as they count about half of the lines.
--
Jarkko
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH 3/3] spi: spi-omap2-mcspi.c: Toggle CS after each word
2013-01-23 18:08 [PATCH 3/3] spi: spi-omap2-mcspi.c: Toggle CS after each word Matthias Brugger
2013-01-24 7:38 ` Jarkko Nikula
@ 2013-01-24 11:06 ` Mark Brown
2013-01-24 22:19 ` Matt Porter
2 siblings, 0 replies; 4+ messages in thread
From: Mark Brown @ 2013-01-24 11:06 UTC (permalink / raw)
To: Matthias Brugger
Cc: Grant Likely, Tony Lindgren, Daniel Mack, Jarkko Nikula,
Greg Kroah-Hartman, eballetbo, javier.martinez, ezequiel.garcia,
spi-devel-general, linux-omap
[-- Attachment #1: Type: text/plain, Size: 494 bytes --]
On Wed, Jan 23, 2013 at 07:08:49PM +0100, Matthias Brugger wrote:
> This patch allows the board code to define SPI devices which needs to
> toggle the chip select after every word send. This is needed to get a
> better resolution reading e.g. an ADC data stream.
> Apart from that, as in the normal code CS is controlled by software,
> a transfer is done much faster.
As Jarkko says the feature itself seems fine and the coding style fix
seems fine but they should really be separate changes.
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH 3/3] spi: spi-omap2-mcspi.c: Toggle CS after each word
2013-01-23 18:08 [PATCH 3/3] spi: spi-omap2-mcspi.c: Toggle CS after each word Matthias Brugger
2013-01-24 7:38 ` Jarkko Nikula
2013-01-24 11:06 ` Mark Brown
@ 2013-01-24 22:19 ` Matt Porter
2 siblings, 0 replies; 4+ messages in thread
From: Matt Porter @ 2013-01-24 22:19 UTC (permalink / raw)
To: Matthias Brugger
Cc: Grant Likely, Mark Brown, Tony Lindgren, Daniel Mack,
Jarkko Nikula, Greg Kroah-Hartman, eballetbo, javier.martinez,
ezequiel.garcia, spi-devel-general, linux-omap
On Wed, Jan 23, 2013 at 07:08:49PM +0100, Matthias Brugger wrote:
> This patch allows the board code to define SPI devices which needs to
> toggle the chip select after every word send. This is needed to get a
> better resolution reading e.g. an ADC data stream.
> Apart from that, as in the normal code CS is controlled by software,
> a transfer is done much faster.
>
> Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
> ---
> drivers/spi/spi-omap2-mcspi.c | 34 ++++++++++++++++++++-------
> include/linux/platform_data/spi-omap2-mcspi.h | 3 +++
> 2 files changed, 29 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c
> index b610f52..12789fc 100644
> --- a/drivers/spi/spi-omap2-mcspi.c
> +++ b/drivers/spi/spi-omap2-mcspi.c
> @@ -927,6 +927,7 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
>
> struct spi_device *spi;
> struct spi_transfer *t = NULL;
> + struct spi_master *master;
> int cs_active = 0;
> struct omap2_mcspi_cs *cs;
> struct omap2_mcspi_device_config *cd;
> @@ -935,6 +936,7 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
> u32 chconf;
>
> spi = m->spi;
> + master = spi->master;
> cs = spi->controller_state;
> cd = spi->controller_data;
>
> @@ -952,6 +954,14 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
> if (!t->speed_hz && !t->bits_per_word)
> par_override = 0;
> }
> + if (cd && cd->cs_per_word) {
> + chconf = mcspi->ctx.modulctrl;
> + chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
> + mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
> + mcspi->ctx.modulctrl =
> + mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
> + }
> +
>
> if (!cs_active) {
> omap2_mcspi_force_cs(spi, 1);
> @@ -1013,6 +1023,14 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
> if (cs_active)
> omap2_mcspi_force_cs(spi, 0);
>
> + if (cd && cd->cs_per_word) {
> + chconf = mcspi->ctx.modulctrl;
> + chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
> + mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
> + mcspi->ctx.modulctrl =
> + mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
> + }
> +
> omap2_mcspi_set_enable(spi, 0);
>
> m->status = status;
> @@ -1020,7 +1038,7 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
> }
>
> static int omap2_mcspi_transfer_one_message(struct spi_master *master,
> - struct spi_message *m)
> + struct spi_message *m)
> {
> struct omap2_mcspi *mcspi;
> struct spi_transfer *t;
> @@ -1041,7 +1059,7 @@ static int omap2_mcspi_transfer_one_message(struct spi_master *master,
> || (len && !(rx_buf || tx_buf))
> || (t->bits_per_word &&
> ( t->bits_per_word < 4
> - || t->bits_per_word > 32))) {
> + || t->bits_per_word > 32))) {
> dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
> t->speed_hz,
> len,
> @@ -1052,8 +1070,8 @@ static int omap2_mcspi_transfer_one_message(struct spi_master *master,
> }
> if (t->speed_hz && t->speed_hz < (OMAP2_MCSPI_MAX_FREQ >> 15)) {
> dev_dbg(mcspi->dev, "speed_hz %d below minimum %d Hz\n",
> - t->speed_hz,
> - OMAP2_MCSPI_MAX_FREQ >> 15);
> + t->speed_hz,
> + OMAP2_MCSPI_MAX_FREQ >> 15);
> return -EINVAL;
> }
>
> @@ -1099,7 +1117,7 @@ static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
> return ret;
>
> mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
> - OMAP2_MCSPI_WAKEUPENABLE_WKEN);
> + OMAP2_MCSPI_WAKEUPENABLE_WKEN);
> ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
>
> omap2_mcspi_set_master_mode(master);
> @@ -1228,7 +1246,7 @@ static int omap2_mcspi_probe(struct platform_device *pdev)
>
> sprintf(dma_ch_name, "rx%d", i);
> dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
> - dma_ch_name);
> + dma_ch_name);
> if (!dma_res) {
> dev_dbg(&pdev->dev, "cannot get DMA RX channel\n");
> status = -ENODEV;
> @@ -1238,7 +1256,7 @@ static int omap2_mcspi_probe(struct platform_device *pdev)
> mcspi->dma_channels[i].dma_rx_sync_dev = dma_res->start;
> sprintf(dma_ch_name, "tx%d", i);
> dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
> - dma_ch_name);
> + dma_ch_name);
> if (!dma_res) {
> dev_dbg(&pdev->dev, "cannot get DMA TX channel\n");
> status = -ENODEV;
> @@ -1254,7 +1272,7 @@ static int omap2_mcspi_probe(struct platform_device *pdev)
> pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
> if (IS_ERR(pinctrl))
> dev_warn(&pdev->dev,
> - "pins are not configured from the driver\n");
> + "pins are not configured from the driver\n");
>
> pm_runtime_use_autosuspend(&pdev->dev);
> pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
> diff --git a/include/linux/platform_data/spi-omap2-mcspi.h b/include/linux/platform_data/spi-omap2-mcspi.h
> index a65572d..c100456 100644
> --- a/include/linux/platform_data/spi-omap2-mcspi.h
> +++ b/include/linux/platform_data/spi-omap2-mcspi.h
> @@ -22,6 +22,9 @@ struct omap2_mcspi_dev_attr {
>
> struct omap2_mcspi_device_config {
> unsigned turbo_mode:1;
> +
> + /* toggle chip select after every word */
> + unsigned cs_per_word:1;
Looks good. It would be also be nice to have an accompanying update to
the DT bindings and parser when adding another attribute like this. Many
platforms using this driver can only boot from DT.
-Matt
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2013-01-24 22:19 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2013-01-23 18:08 [PATCH 3/3] spi: spi-omap2-mcspi.c: Toggle CS after each word Matthias Brugger
2013-01-24 7:38 ` Jarkko Nikula
2013-01-24 11:06 ` Mark Brown
2013-01-24 22:19 ` Matt Porter
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.