1 files changed, 106 insertions, 53 deletions

diff --git a/drivers/spi/spi_s3c24xx.c b/drivers/spi/spi_s3c24xx.c
index 3f3119d760db..33d94f76b9ef 100644
--- a/drivers/spi/spi_s3c24xx.c
+++ b/drivers/spi/spi_s3c24xx.c
@@ -20,17 +20,28 @@
 #include <linux/clk.h>
 #include <linux/platform_device.h>
 #include <linux/gpio.h>
+#include <linux/io.h>
 
 #include <linux/spi/spi.h>
 #include <linux/spi/spi_bitbang.h>
 
-#include <asm/io.h>
-#include <asm/dma.h>
-#include <mach/hardware.h>
-
 #include <plat/regs-spi.h>
 #include <mach/spi.h>
 
+/**
+ * s3c24xx_spi_devstate - per device data
+ * @hz: Last frequency calculated for @sppre field.
+ * @mode: Last mode setting for the @spcon field.
+ * @spcon: Value to write to the SPCON register.
+ * @sppre: Value to write to the SPPRE register.
+ */
+struct s3c24xx_spi_devstate {
+        unsigned int    hz;
+        unsigned int    mode;
+        u8              spcon;
+        u8              sppre;
+};
+
 struct s3c24xx_spi {
         /* bitbang has to be first */
         struct spi_bitbang       bitbang;
@@ -71,43 +82,31 @@ static void s3c24xx_spi_gpiocs(struct s3c2410_spi_info *spi, int cs, int pol)
 
 static void s3c24xx_spi_chipsel(struct spi_device *spi, int value)
 {
+        struct s3c24xx_spi_devstate *cs = spi->controller_state;
         struct s3c24xx_spi *hw = to_hw(spi);
         unsigned int cspol = spi->mode & SPI_CS_HIGH ? 1 : 0;
-        unsigned int spcon;
+
+        /* change the chipselect state and the state of the spi engine clock */
 
         switch (value) {
         case BITBANG_CS_INACTIVE:
                 hw->set_cs(hw->pdata, spi->chip_select, cspol^1);
+                writeb(cs->spcon, hw->regs + S3C2410_SPCON);
                 break;
 
         case BITBANG_CS_ACTIVE:
-                spcon = readb(hw->regs + S3C2410_SPCON);
-
-                if (spi->mode & SPI_CPHA)
-                        spcon |= S3C2410_SPCON_CPHA_FMTB;
-                else
-                        spcon &= ~S3C2410_SPCON_CPHA_FMTB;
-
-                if (spi->mode & SPI_CPOL)
-                        spcon |= S3C2410_SPCON_CPOL_HIGH;
-                else
-                        spcon &= ~S3C2410_SPCON_CPOL_HIGH;
-
-                spcon |= S3C2410_SPCON_ENSCK;
-
-                /* write new configration */
-
-                writeb(spcon, hw->regs + S3C2410_SPCON);
+                writeb(cs->spcon | S3C2410_SPCON_ENSCK,
+                       hw->regs + S3C2410_SPCON);
                 hw->set_cs(hw->pdata, spi->chip_select, cspol);
-
                 break;
         }
 }
 
-static int s3c24xx_spi_setupxfer(struct spi_device *spi,
-                                 struct spi_transfer *t)
+static int s3c24xx_spi_update_state(struct spi_device *spi,
+                                    struct spi_transfer *t)
 {
         struct s3c24xx_spi *hw = to_hw(spi);
+        struct s3c24xx_spi_devstate *cs = spi->controller_state;
         unsigned int bpw;
         unsigned int hz;
         unsigned int div;
@@ -127,41 +126,89 @@ static int s3c24xx_spi_setupxfer(struct spi_device *spi,
                 return -EINVAL;
         }
 
-        clk = clk_get_rate(hw->clk);
-        div = DIV_ROUND_UP(clk, hz * 2) - 1;
+        if (spi->mode != cs->mode) {
+                u8 spcon = SPCON_DEFAULT;
 
-        if (div > 255)
-                div = 255;
+                if (spi->mode & SPI_CPHA)
+                        spcon |= S3C2410_SPCON_CPHA_FMTB;
 
-        dev_dbg(&spi->dev, "setting pre-scaler to %d (wanted %d, got %ld)\n",
-                div, hz, clk / (2 * (div + 1)));
+                if (spi->mode & SPI_CPOL)
+                        spcon |= S3C2410_SPCON_CPOL_HIGH;
 
+                cs->mode = spi->mode;
+                cs->spcon = spcon;
+        }
 
-        writeb(div, hw->regs + S3C2410_SPPRE);
+        if (cs->hz != hz) {
+                clk = clk_get_rate(hw->clk);
+                div = DIV_ROUND_UP(clk, hz * 2) - 1;
 
-        spin_lock(&hw->bitbang.lock);
-        if (!hw->bitbang.busy) {
-                hw->bitbang.chipselect(spi, BITBANG_CS_INACTIVE);
-                /* need to ndelay for 0.5 clocktick ? */
+                if (div > 255)
+                        div = 255;
+
+                dev_dbg(&spi->dev, "pre-scaler=%d (wanted %d, got %ld)\n",
+                        div, hz, clk / (2 * (div + 1)));
+
+                cs->hz = hz;
+                cs->sppre = div;
         }
-        spin_unlock(&hw->bitbang.lock);
 
         return 0;
 }
 
+static int s3c24xx_spi_setupxfer(struct spi_device *spi,
+                                 struct spi_transfer *t)
+{
+        struct s3c24xx_spi_devstate *cs = spi->controller_state;
+        struct s3c24xx_spi *hw = to_hw(spi);
+        int ret;
+
+        ret = s3c24xx_spi_update_state(spi, t);
+        if (!ret)
+                writeb(cs->sppre, hw->regs + S3C2410_SPPRE);
+
+        return ret;
+}
+
 static int s3c24xx_spi_setup(struct spi_device *spi)
 {
+        struct s3c24xx_spi_devstate *cs = spi->controller_state;
+        struct s3c24xx_spi *hw = to_hw(spi);
         int ret;
 
-        ret = s3c24xx_spi_setupxfer(spi, NULL);
-        if (ret < 0) {
-                dev_err(&spi->dev, "setupxfer returned %d\n", ret);
+        /* allocate settings on the first call */
+        if (!cs) {
+                cs = kzalloc(sizeof(struct s3c24xx_spi_devstate), GFP_KERNEL);
+                if (!cs) {
+                        dev_err(&spi->dev, "no memory for controller state\n");
+                        return -ENOMEM;
+                }
+
+                cs->spcon = SPCON_DEFAULT;
+                cs->hz = -1;
+                spi->controller_state = cs;
+        }
+
+        /* initialise the state from the device */
+        ret = s3c24xx_spi_update_state(spi, NULL);
+        if (ret)
                 return ret;
+
+        spin_lock(&hw->bitbang.lock);
+        if (!hw->bitbang.busy) {
+                hw->bitbang.chipselect(spi, BITBANG_CS_INACTIVE);
+                /* need to ndelay for 0.5 clocktick ? */
         }
+        spin_unlock(&hw->bitbang.lock);
 
         return 0;
 }
 
+static void s3c24xx_spi_cleanup(struct spi_device *spi)
+{
+        kfree(spi->controller_state);
+}
+
 static inline unsigned int hw_txbyte(struct s3c24xx_spi *hw, int count)
 {
         return hw->tx ? hw->tx[count] : 0;
@@ -289,7 +336,9 @@ static int __init s3c24xx_spi_probe(struct platform_device *pdev)
         hw->bitbang.setup_transfer = s3c24xx_spi_setupxfer;
         hw->bitbang.chipselect     = s3c24xx_spi_chipsel;
         hw->bitbang.txrx_bufs      = s3c24xx_spi_txrx;
-        hw->bitbang.master->setup  = s3c24xx_spi_setup;
+
+        hw->master->setup  = s3c24xx_spi_setup;
+        hw->master->cleanup = s3c24xx_spi_cleanup;
 
         dev_dbg(hw->dev, "bitbang at %p\n", &hw->bitbang);
 
@@ -302,7 +351,7 @@ static int __init s3c24xx_spi_probe(struct platform_device *pdev)
                 goto err_no_iores;
         }
 
-        hw->ioarea = request_mem_region(res->start, (res->end - res->start)+1,
+        hw->ioarea = request_mem_region(res->start, resource_size(res),
                                         pdev->name);
 
         if (hw->ioarea == NULL) {
@@ -311,7 +360,7 @@ static int __init s3c24xx_spi_probe(struct platform_device *pdev)
                 goto err_no_iores;
         }
 
-        hw->regs = ioremap(res->start, (res->end - res->start)+1);
+        hw->regs = ioremap(res->start, resource_size(res));
         if (hw->regs == NULL) {
                 dev_err(&pdev->dev, "Cannot map IO\n");
                 err = -ENXIO;
@@ -388,7 +437,7 @@ static int __init s3c24xx_spi_probe(struct platform_device *pdev)
 
  err_no_iores:
  err_no_pdata:
-        spi_master_put(hw->master);;
+        spi_master_put(hw->master);
 
  err_nomem:
         return err;
@@ -421,9 +470,9 @@ static int __exit s3c24xx_spi_remove(struct platform_device *dev)
 
 #ifdef CONFIG_PM
 
-static int s3c24xx_spi_suspend(struct platform_device *pdev, pm_message_t msg)
+static int s3c24xx_spi_suspend(struct device *dev)
 {
-        struct s3c24xx_spi *hw = platform_get_drvdata(pdev);
+        struct s3c24xx_spi *hw = platform_get_drvdata(to_platform_device(dev));
 
         if (hw->pdata && hw->pdata->gpio_setup)
                 hw->pdata->gpio_setup(hw->pdata, 0);
@@ -432,27 +481,31 @@ static int s3c24xx_spi_suspend(struct platform_device *pdev, pm_message_t msg)
         return 0;
 }
 
-static int s3c24xx_spi_resume(struct platform_device *pdev)
+static int s3c24xx_spi_resume(struct device *dev)
 {
-        struct s3c24xx_spi *hw = platform_get_drvdata(pdev);
+        struct s3c24xx_spi *hw = platform_get_drvdata(to_platform_device(dev));
 
         s3c24xx_spi_initialsetup(hw);
         return 0;
 }
 
+static struct dev_pm_ops s3c24xx_spi_pmops = {
+        .suspend        = s3c24xx_spi_suspend,
+        .resume         = s3c24xx_spi_resume,
+};
+
+#define S3C24XX_SPI_PMOPS &s3c24xx_spi_pmops
 #else
-#define s3c24xx_spi_suspend NULL
-#define s3c24xx_spi_resume  NULL
-#endif
+#define S3C24XX_SPI_PMOPS NULL
+#endif /* CONFIG_PM */
 
 MODULE_ALIAS("platform:s3c2410-spi");
 static struct platform_driver s3c24xx_spi_driver = {
         .remove         = __exit_p(s3c24xx_spi_remove),
-        .suspend        = s3c24xx_spi_suspend,
-        .resume         = s3c24xx_spi_resume,
         .driver         = {
                 .name   = "s3c2410-spi",
                 .owner  = THIS_MODULE,
+                .pm     = S3C24XX_SPI_PMOPS,
         },
 };