Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
[linux-2.6-block.git] / drivers / spi / spi_s3c24xx.c
index 3f3119d760db71fc653b75e77615ce8069b7c300..33d94f76b9ef47fd92bddd54815e72262b6dffda 100644 (file)
 #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,
        },
 };