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From b875f877d06acb852342636db4c3d1e6c9fe01ba Mon Sep 17 00:00:00 2001
From: Gabor Juhos <juhosg@openwrt.org>
Date: Wed, 11 Jan 2012 22:25:11 +0100
Subject: [PATCH 7/7] spi/ath79: make chipselect logic more flexible
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
---
.../include/asm/mach-ath79/ath79_spi_platform.h | 8 ++-
drivers/spi/spi-ath79.c | 65 +++++++++++--------
2 files changed, 45 insertions(+), 28 deletions(-)
--- a/arch/mips/include/asm/mach-ath79/ath79_spi_platform.h
+++ b/arch/mips/include/asm/mach-ath79/ath79_spi_platform.h
@@ -16,8 +16,14 @@ struct ath79_spi_platform_data {
unsigned num_chipselect;
};
+enum ath79_spi_cs_type {
+ ATH79_SPI_CS_TYPE_INTERNAL,
+ ATH79_SPI_CS_TYPE_GPIO,
+};
+
struct ath79_spi_controller_data {
- unsigned gpio;
+ enum ath79_spi_cs_type cs_type;
+ unsigned cs_line;
};
#endif /* _ATH79_SPI_PLATFORM_H */
--- a/drivers/spi/spi-ath79.c
+++ b/drivers/spi/spi-ath79.c
@@ -30,6 +30,8 @@
#define DRV_NAME "ath79-spi"
+#define ATH79_SPI_CS_LINE_MAX 2
+
struct ath79_spi {
struct spi_bitbang bitbang;
u32 ioc_base;
@@ -62,6 +64,7 @@ static void ath79_spi_chipselect(struct
{
struct ath79_spi *sp = ath79_spidev_to_sp(spi);
int cs_high = (spi->mode & SPI_CS_HIGH) ? is_active : !is_active;
+ struct ath79_spi_controller_data *cdata = spi->controller_data;
if (is_active) {
/* set initial clock polarity */
@@ -73,20 +76,21 @@ static void ath79_spi_chipselect(struct
ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, sp->ioc_base);
}
- if (spi->chip_select) {
- struct ath79_spi_controller_data *cdata = spi->controller_data;
-
- /* SPI is normally active-low */
- gpio_set_value(cdata->gpio, cs_high);
- } else {
+ switch (cdata->cs_type) {
+ case ATH79_SPI_CS_TYPE_INTERNAL:
if (cs_high)
- sp->ioc_base |= AR71XX_SPI_IOC_CS0;
+ sp->ioc_base |= AR71XX_SPI_IOC_CS(cdata->cs_line);
else
- sp->ioc_base &= ~AR71XX_SPI_IOC_CS0;
+ sp->ioc_base &= ~AR71XX_SPI_IOC_CS(cdata->cs_line);
ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, sp->ioc_base);
- }
+ break;
+ case ATH79_SPI_CS_TYPE_GPIO:
+ /* SPI is normally active-low */
+ gpio_set_value(cdata->cs_line, cs_high);
+ break;
+ }
}
static void ath79_spi_enable(struct ath79_spi *sp)
@@ -113,24 +117,30 @@ static void ath79_spi_disable(struct ath
static int ath79_spi_setup_cs(struct spi_device *spi)
{
struct ath79_spi_controller_data *cdata;
+ unsigned long flags;
int status;
cdata = spi->controller_data;
- if (spi->chip_select && !cdata)
+ if (!cdata)
return -EINVAL;
status = 0;
- if (spi->chip_select) {
- unsigned long flags;
+ switch (cdata->cs_type) {
+ case ATH79_SPI_CS_TYPE_INTERNAL:
+ if (cdata->cs_line > ATH79_SPI_CS_LINE_MAX)
+ status = -EINVAL;
+ break;
+ case ATH79_SPI_CS_TYPE_GPIO:
flags = GPIOF_DIR_OUT;
if (spi->mode & SPI_CS_HIGH)
flags |= GPIOF_INIT_HIGH;
else
flags |= GPIOF_INIT_LOW;
- status = gpio_request_one(cdata->gpio, flags,
+ status = gpio_request_one(cdata->cs_line, flags,
dev_name(&spi->dev));
+ break;
}
return status;
@@ -138,9 +148,15 @@ static int ath79_spi_setup_cs(struct spi
static void ath79_spi_cleanup_cs(struct spi_device *spi)
{
- if (spi->chip_select) {
- struct ath79_spi_controller_data *cdata = spi->controller_data;
- gpio_free(cdata->gpio);
+ struct ath79_spi_controller_data *cdata = spi->controller_data;
+
+ switch (cdata->cs_type) {
+ case ATH79_SPI_CS_TYPE_INTERNAL:
+ /* nothing to do */
+ break;
+ case ATH79_SPI_CS_TYPE_GPIO:
+ gpio_free(cdata->cs_line);
+ break;
}
}
@@ -206,6 +222,10 @@ static __devinit int ath79_spi_probe(str
struct resource *r;
int ret;
+ pdata = pdev->dev.platform_data;
+ if (!pdata)
+ return -EINVAL;
+
master = spi_alloc_master(&pdev->dev, sizeof(*sp));
if (master == NULL) {
dev_err(&pdev->dev, "failed to allocate spi master\n");
@@ -215,17 +235,10 @@ static __devinit int ath79_spi_probe(str
sp = spi_master_get_devdata(master);
platform_set_drvdata(pdev, sp);
- pdata = pdev->dev.platform_data;
-
master->setup = ath79_spi_setup;
master->cleanup = ath79_spi_cleanup;
- if (pdata) {
- master->bus_num = pdata->bus_num;
- master->num_chipselect = pdata->num_chipselect;
- } else {
- master->bus_num = -1;
- master->num_chipselect = 1;
- }
+ master->bus_num = pdata->bus_num;
+ master->num_chipselect = pdata->num_chipselect;
sp->bitbang.master = spi_master_get(master);
sp->bitbang.chipselect = ath79_spi_chipselect;
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