Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus

[pandora-kernel.git] / drivers / spi / spi_gpio.c

diff --git a/drivers/spi/spi_gpio.c b/drivers/spi/spi_gpio.c
index 7edbd58..63e51b0 100644 (file)
--- a/drivers/spi/spi_gpio.c
+++ b/drivers/spi/spi_gpio.c
@@ -146,25 +146,63 @@ static inline int getmiso(const struct spi_device *spi)
 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);
+}
+
+/*
+ * 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);
 }
 
 /*----------------------------------------------------------------------*/
@@ -232,19 +270,30 @@ static int __init spi_gpio_alloc(unsigned pin, const char *label, bool is_in)
 }
 
 static int __init
-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;
+       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;
+       }
 
-       value = spi_gpio_alloc(SPI_MISO_GPIO, label, true);
-       if (value)
-               goto free_mosi;
+       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)
@@ -253,9 +302,11 @@ spi_gpio_request(struct spi_gpio_platform_data *pdata, const char *label)
        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;
 }
@@ -266,6 +317,7 @@ static int __init spi_gpio_probe(struct platform_device *pdev)
        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
@@ -273,7 +325,7 @@ static int __init spi_gpio_probe(struct platform_device *pdev)
                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;
 
@@ -289,6 +341,7 @@ static int __init spi_gpio_probe(struct platform_device *pdev)
        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;
@@ -296,10 +349,18 @@ static int __init spi_gpio_probe(struct platform_device *pdev)
 
        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_TX | 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;
 
@@ -307,8 +368,10 @@ static int __init spi_gpio_probe(struct platform_device *pdev)
        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);
        }
@@ -331,8 +394,10 @@ static int __exit spi_gpio_remove(struct platform_device *pdev)
 
        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;