backport SPI master with no RXTX support (from 2.6.36)

Signed-off-by: Miguel Gaio <miguel.gaio@efixo.com>

SVN-Revision: 23498
This commit is contained in:
Florian Fainelli 2010-10-17 14:08:39 +00:00
parent d5854cfd4d
commit cd9b90235c
2 changed files with 454 additions and 0 deletions

View file

@ -0,0 +1,237 @@
From 04bb2a031cf95b34b7432dd47b318a932a895b4c Mon Sep 17 00:00:00 2001
From: Marek Szyprowski <m.szyprowski@samsung.com>
Date: Wed, 30 Jun 2010 14:27:32 -0600
Subject: [PATCH] spi/bitbang: add support for SPI_MASTER_NO_{TX, RX} modes
This patch adds a new flags argument to bitbang_txrx_be_cpha0 and
bitbang_txrx_be_cpha1 transfer functions. This enables support for
SPI_MASTER_NO_{TX,RX} transfer modes. The change should have no impact
on speed of the existing drivers. bitbank_txrx_* functions are usually
inlined into the drivers. When the argument is equal to constant zero,
the optimizer would be able to eliminate the dead code (flags checks)
easily. Tested on ARM and GCC 4.4.x and in all cases the checks were
eliminated in the inlined function.
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
---
drivers/spi/spi_bitbang_txrx.h | 16 ++++++++++------
drivers/spi/spi_butterfly.c | 2 +-
drivers/spi/spi_gpio.c | 8 ++++----
drivers/spi/spi_lm70llp.c | 2 +-
drivers/spi/spi_s3c24xx_gpio.c | 8 ++++----
drivers/spi/spi_sh_sci.c | 8 ++++----
6 files changed, 24 insertions(+), 20 deletions(-)
--- a/drivers/spi/spi_bitbang_txrx.h
+++ b/drivers/spi/spi_bitbang_txrx.h
@@ -44,7 +44,7 @@
static inline u32
bitbang_txrx_be_cpha0(struct spi_device *spi,
- unsigned nsecs, unsigned cpol,
+ unsigned nsecs, unsigned cpol, unsigned flags,
u32 word, u8 bits)
{
/* if (cpol == 0) this is SPI_MODE_0; else this is SPI_MODE_2 */
@@ -53,7 +53,8 @@ bitbang_txrx_be_cpha0(struct spi_device
for (word <<= (32 - bits); likely(bits); bits--) {
/* setup MSB (to slave) on trailing edge */
- setmosi(spi, word & (1 << 31));
+ if ((flags & SPI_MASTER_NO_TX) == 0)
+ setmosi(spi, word & (1 << 31));
spidelay(nsecs); /* T(setup) */
setsck(spi, !cpol);
@@ -61,7 +62,8 @@ bitbang_txrx_be_cpha0(struct spi_device
/* sample MSB (from slave) on leading edge */
word <<= 1;
- word |= getmiso(spi);
+ if ((flags & SPI_MASTER_NO_RX) == 0)
+ word |= getmiso(spi);
setsck(spi, cpol);
}
return word;
@@ -69,7 +71,7 @@ bitbang_txrx_be_cpha0(struct spi_device
static inline u32
bitbang_txrx_be_cpha1(struct spi_device *spi,
- unsigned nsecs, unsigned cpol,
+ unsigned nsecs, unsigned cpol, unsigned flags,
u32 word, u8 bits)
{
/* if (cpol == 0) this is SPI_MODE_1; else this is SPI_MODE_3 */
@@ -79,7 +81,8 @@ bitbang_txrx_be_cpha1(struct spi_device
/* setup MSB (to slave) on leading edge */
setsck(spi, !cpol);
- setmosi(spi, word & (1 << 31));
+ if ((flags & SPI_MASTER_NO_TX) == 0)
+ setmosi(spi, word & (1 << 31));
spidelay(nsecs); /* T(setup) */
setsck(spi, cpol);
@@ -87,7 +90,8 @@ bitbang_txrx_be_cpha1(struct spi_device
/* sample MSB (from slave) on trailing edge */
word <<= 1;
- word |= getmiso(spi);
+ if ((flags & SPI_MASTER_NO_RX) == 0)
+ word |= getmiso(spi);
}
return word;
}
--- a/drivers/spi/spi_butterfly.c
+++ b/drivers/spi/spi_butterfly.c
@@ -156,7 +156,7 @@ butterfly_txrx_word_mode0(struct spi_dev
unsigned nsecs,
u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
}
/*----------------------------------------------------------------------*/
--- a/drivers/spi/spi_gpio.c
+++ b/drivers/spi/spi_gpio.c
@@ -157,25 +157,25 @@ static inline void spidelay(unsigned nse
static u32 spi_gpio_txrx_word_mode0(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
}
static u32 spi_gpio_txrx_word_mode1(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits);
}
static u32 spi_gpio_txrx_word_mode2(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits);
}
static u32 spi_gpio_txrx_word_mode3(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits);
}
/*----------------------------------------------------------------------*/
--- a/drivers/spi/spi_lm70llp.c
+++ b/drivers/spi/spi_lm70llp.c
@@ -191,7 +191,7 @@ static void lm70_chipselect(struct spi_d
*/
static u32 lm70_txrx(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
}
static void spi_lm70llp_attach(struct parport *p)
--- a/drivers/spi/spi_s3c24xx_gpio.c
+++ b/drivers/spi/spi_s3c24xx_gpio.c
@@ -64,25 +64,25 @@ static inline u32 getmiso(struct spi_dev
static u32 s3c2410_spigpio_txrx_mode0(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
}
static u32 s3c2410_spigpio_txrx_mode1(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits);
}
static u32 s3c2410_spigpio_txrx_mode2(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits);
}
static u32 s3c2410_spigpio_txrx_mode3(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits);
}
--- a/drivers/spi/spi_sh_sci.c
+++ b/drivers/spi/spi_sh_sci.c
@@ -83,25 +83,25 @@ static inline u32 getmiso(struct spi_dev
static u32 sh_sci_spi_txrx_mode0(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
}
static u32 sh_sci_spi_txrx_mode1(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits);
}
static u32 sh_sci_spi_txrx_mode2(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits);
}
static u32 sh_sci_spi_txrx_mode3(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits);
}
static void sh_sci_spi_chipselect(struct spi_device *dev, int value)
--- a/drivers/spi/spi_gpio_old.c
+++ b/drivers/spi/spi_gpio_old.c
@@ -80,25 +80,25 @@ static inline void do_spidelay(struct sp
static u32 spi_gpio_txrx_mode0(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits);
}
static u32 spi_gpio_txrx_mode1(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits);
}
static u32 spi_gpio_txrx_mode2(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha0(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits);
}
static u32 spi_gpio_txrx_mode3(struct spi_device *spi,
unsigned nsecs, u32 word, u8 bits)
{
- return bitbang_txrx_be_cpha1(spi, nsecs, 1, word, bits);
+ return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits);
}
static void spi_gpio_chipselect(struct spi_device *dev, int on)

View file

@ -0,0 +1,217 @@
From 3c8e1a84fd6b984a7bce8816db2e3defc57bbfe4 Mon Sep 17 00:00:00 2001
From: Marek Szyprowski <m.szyprowski@samsung.com>
Date: Wed, 30 Jun 2010 14:27:37 -0600
Subject: [PATCH] spi/spi-gpio: add support for controllers without MISO or MOSI pin
There are some boards that do not strictly follow SPI standard and use
only 3 wires (SCLK, MOSI or MISO, SS) for connecting some simple auxiliary
chips and controls them with GPIO based 'spi controller'. In this
configuration the MISO or MOSI line is missing (it is not required if the
chip does not transfer any data back to host or host only reads data from
chip).
This patch adds support for such non-standard configuration in GPIO-based
SPI controller. It has been tested in configuration without MISO pin.
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
---
drivers/spi/spi_gpio.c | 101 ++++++++++++++++++++++++++++++++++-------
include/linux/spi/spi_gpio.h | 5 ++
2 files changed, 88 insertions(+), 18 deletions(-)
--- a/drivers/spi/spi_gpio.c
+++ b/drivers/spi/spi_gpio.c
@@ -178,6 +178,44 @@ static u32 spi_gpio_txrx_word_mode3(stru
return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits);
}
+/*
+ * These functions do not call setmosi or getmiso if respective flag
+ * (SPI_MASTER_NO_RX or SPI_MASTER_NO_TX) is set, so they are safe to
+ * call when such pin is not present or defined in the controller.
+ * A separate set of callbacks is defined to get highest possible
+ * speed in the generic case (when both MISO and MOSI lines are
+ * available), as optimiser will remove the checks when argument is
+ * constant.
+ */
+
+static u32 spi_gpio_spec_txrx_word_mode0(struct spi_device *spi,
+ unsigned nsecs, u32 word, u8 bits)
+{
+ unsigned flags = spi->master->flags;
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, flags, word, bits);
+}
+
+static u32 spi_gpio_spec_txrx_word_mode1(struct spi_device *spi,
+ unsigned nsecs, u32 word, u8 bits)
+{
+ unsigned flags = spi->master->flags;
+ return bitbang_txrx_be_cpha1(spi, nsecs, 0, flags, word, bits);
+}
+
+static u32 spi_gpio_spec_txrx_word_mode2(struct spi_device *spi,
+ unsigned nsecs, u32 word, u8 bits)
+{
+ unsigned flags = spi->master->flags;
+ return bitbang_txrx_be_cpha0(spi, nsecs, 1, flags, word, bits);
+}
+
+static u32 spi_gpio_spec_txrx_word_mode3(struct spi_device *spi,
+ unsigned nsecs, u32 word, u8 bits)
+{
+ unsigned flags = spi->master->flags;
+ return bitbang_txrx_be_cpha1(spi, nsecs, 1, flags, word, bits);
+}
+
/*----------------------------------------------------------------------*/
static void spi_gpio_chipselect(struct spi_device *spi, int is_active)
@@ -243,19 +281,30 @@ static int __devinit spi_gpio_alloc(unsi
}
static int __devinit
-spi_gpio_request(struct spi_gpio_platform_data *pdata, const char *label)
+spi_gpio_request(struct spi_gpio_platform_data *pdata, const char *label,
+ u16 *res_flags)
{
int value;
/* NOTE: SPI_*_GPIO symbols may reference "pdata" */
- value = spi_gpio_alloc(SPI_MOSI_GPIO, label, false);
- if (value)
- goto done;
-
- value = spi_gpio_alloc(SPI_MISO_GPIO, label, true);
- if (value)
- goto free_mosi;
+ if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) {
+ value = spi_gpio_alloc(SPI_MOSI_GPIO, label, false);
+ if (value)
+ goto done;
+ } else {
+ /* HW configuration without MOSI pin */
+ *res_flags |= SPI_MASTER_NO_TX;
+ }
+
+ if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) {
+ value = spi_gpio_alloc(SPI_MISO_GPIO, label, true);
+ if (value)
+ goto free_mosi;
+ } else {
+ /* HW configuration without MISO pin */
+ *res_flags |= SPI_MASTER_NO_RX;
+ }
value = spi_gpio_alloc(SPI_SCK_GPIO, label, false);
if (value)
@@ -264,9 +313,11 @@ spi_gpio_request(struct spi_gpio_platfor
goto done;
free_miso:
- gpio_free(SPI_MISO_GPIO);
+ if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO)
+ gpio_free(SPI_MISO_GPIO);
free_mosi:
- gpio_free(SPI_MOSI_GPIO);
+ if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI)
+ gpio_free(SPI_MOSI_GPIO);
done:
return value;
}
@@ -277,6 +328,7 @@ static int __devinit spi_gpio_probe(stru
struct spi_master *master;
struct spi_gpio *spi_gpio;
struct spi_gpio_platform_data *pdata;
+ u16 master_flags = 0;
pdata = pdev->dev.platform_data;
#ifdef GENERIC_BITBANG
@@ -284,7 +336,7 @@ static int __devinit spi_gpio_probe(stru
return -ENODEV;
#endif
- status = spi_gpio_request(pdata, dev_name(&pdev->dev));
+ status = spi_gpio_request(pdata, dev_name(&pdev->dev), &master_flags);
if (status < 0)
return status;
@@ -300,6 +352,7 @@ static int __devinit spi_gpio_probe(stru
if (pdata)
spi_gpio->pdata = *pdata;
+ master->flags = master_flags;
master->bus_num = pdev->id;
master->num_chipselect = SPI_N_CHIPSEL;
master->setup = spi_gpio_setup;
@@ -307,10 +360,18 @@ static int __devinit spi_gpio_probe(stru
spi_gpio->bitbang.master = spi_master_get(master);
spi_gpio->bitbang.chipselect = spi_gpio_chipselect;
- spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_word_mode0;
- spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_txrx_word_mode1;
- spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_txrx_word_mode2;
- spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_txrx_word_mode3;
+
+ if ((master_flags & (SPI_MASTER_NO_RX | SPI_MASTER_NO_RX)) == 0) {
+ spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_word_mode0;
+ spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_txrx_word_mode1;
+ spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_txrx_word_mode2;
+ spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_txrx_word_mode3;
+ } else {
+ spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_spec_txrx_word_mode0;
+ spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_spec_txrx_word_mode1;
+ spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_spec_txrx_word_mode2;
+ spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_spec_txrx_word_mode3;
+ }
spi_gpio->bitbang.setup_transfer = spi_bitbang_setup_transfer;
spi_gpio->bitbang.flags = SPI_CS_HIGH;
@@ -318,8 +379,10 @@ static int __devinit spi_gpio_probe(stru
if (status < 0) {
spi_master_put(spi_gpio->bitbang.master);
gpio_free:
- gpio_free(SPI_MISO_GPIO);
- gpio_free(SPI_MOSI_GPIO);
+ if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO)
+ gpio_free(SPI_MISO_GPIO);
+ if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI)
+ gpio_free(SPI_MOSI_GPIO);
gpio_free(SPI_SCK_GPIO);
spi_master_put(master);
}
@@ -342,8 +405,10 @@ static int __devexit spi_gpio_remove(str
platform_set_drvdata(pdev, NULL);
- gpio_free(SPI_MISO_GPIO);
- gpio_free(SPI_MOSI_GPIO);
+ if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO)
+ gpio_free(SPI_MISO_GPIO);
+ if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI)
+ gpio_free(SPI_MOSI_GPIO);
gpio_free(SPI_SCK_GPIO);
return status;
--- a/include/linux/spi/spi_gpio.h
+++ b/include/linux/spi/spi_gpio.h
@@ -29,11 +29,16 @@
* SPI_GPIO_NO_CHIPSELECT to the controller_data:
* .controller_data = (void *) SPI_GPIO_NO_CHIPSELECT;
*
+ * If the MISO or MOSI pin is not available then it should be set to
+ * SPI_GPIO_NO_MISO or SPI_GPIO_NO_MOSI.
+ *
* If the bitbanged bus is later switched to a "native" controller,
* that platform_device and controller_data should be removed.
*/
#define SPI_GPIO_NO_CHIPSELECT ((unsigned long)-1l)
+#define SPI_GPIO_NO_MISO ((unsigned long)-1l)
+#define SPI_GPIO_NO_MOSI ((unsigned long)-1l)
/**
* struct spi_gpio_platform_data - parameter for bitbanged SPI master