[ARM] pxa: update PXA MMC interface driver to use clk support
authorRussell King <rmk@dyn-67.arm.linux.org.uk>
Mon, 20 Aug 2007 09:20:03 +0000 (10:20 +0100)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Fri, 12 Oct 2007 20:15:03 +0000 (21:15 +0100)
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
drivers/mmc/host/pxamci.c
drivers/mmc/host/pxamci.h

index 657901eecfced1b6222d2f772a81415a5b836eaa..0601e01aa2c20e1faf576015ad441ce695388dd6 100644 (file)
@@ -23,6 +23,8 @@
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/dma-mapping.h>
+#include <linux/clk.h>
+#include <linux/err.h>
 #include <linux/mmc/host.h>
 
 #include <asm/dma.h>
@@ -44,6 +46,8 @@ struct pxamci_host {
        spinlock_t              lock;
        struct resource         *res;
        void __iomem            *base;
+       struct clk              *clk;
+       unsigned long           clkrate;
        int                     irq;
        int                     dma;
        unsigned int            clkrt;
@@ -119,7 +123,7 @@ static void pxamci_setup_data(struct pxamci_host *host, struct mmc_data *data)
        writel(nob, host->base + MMC_NOB);
        writel(data->blksz, host->base + MMC_BLKLEN);
 
-       clks = (unsigned long long)data->timeout_ns * CLOCKRATE;
+       clks = (unsigned long long)data->timeout_ns * host->clkrate;
        do_div(clks, 1000000000UL);
        timeout = (unsigned int)clks + (data->timeout_clks << host->clkrt);
        writel((timeout + 255) / 256, host->base + MMC_RDTO);
@@ -365,18 +369,25 @@ static void pxamci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
        struct pxamci_host *host = mmc_priv(mmc);
 
        if (ios->clock) {
-               unsigned int clk = CLOCKRATE / ios->clock;
-               if (CLOCKRATE / clk > ios->clock)
+               unsigned long rate = host->clkrate;
+               unsigned int clk = rate / ios->clock;
+
+               /*
+                * clk might result in a lower divisor than we
+                * desire.  check for that condition and adjust
+                * as appropriate.
+                */
+               if (rate / clk > ios->clock)
                        clk <<= 1;
                host->clkrt = fls(clk) - 1;
-               pxa_set_cken(CKEN_MMC, 1);
+               clk_enable(host->clk);
 
                /*
                 * we write clkrt on the next command
                 */
        } else {
                pxamci_stop_clock(host);
-               pxa_set_cken(CKEN_MMC, 0);
+               clk_disable(host->clk);
        }
 
        if (host->power_mode != ios->power_mode) {
@@ -462,8 +473,6 @@ static int pxamci_probe(struct platform_device *pdev)
        }
 
        mmc->ops = &pxamci_ops;
-       mmc->f_min = CLOCKRATE_MIN;
-       mmc->f_max = CLOCKRATE_MAX;
 
        /*
         * We can do SG-DMA, but we don't because we never know how much
@@ -490,6 +499,22 @@ static int pxamci_probe(struct platform_device *pdev)
        host->mmc = mmc;
        host->dma = -1;
        host->pdata = pdev->dev.platform_data;
+
+       host->clk = clk_get(&pdev->dev, "MMCCLK");
+       if (IS_ERR(host->clk)) {
+               ret = PTR_ERR(host->clk);
+               host->clk = NULL;
+               goto out;
+       }
+
+       host->clkrate = clk_get_rate(host->clk);
+
+       /*
+        * Calculate minimum clock rate, rounding up.
+        */
+       mmc->f_min = (host->clkrate + 63) / 64;
+       mmc->f_max = host->clkrate;
+
        mmc->ocr_avail = host->pdata ?
                         host->pdata->ocr_mask :
                         MMC_VDD_32_33|MMC_VDD_33_34;
@@ -554,6 +579,8 @@ static int pxamci_probe(struct platform_device *pdev)
                        iounmap(host->base);
                if (host->sg_cpu)
                        dma_free_coherent(&pdev->dev, PAGE_SIZE, host->sg_cpu, host->sg_dma);
+               if (host->clk)
+                       clk_put(host->clk);
        }
        if (mmc)
                mmc_free_host(mmc);
@@ -588,6 +615,8 @@ static int pxamci_remove(struct platform_device *pdev)
                iounmap(host->base);
                dma_free_coherent(&pdev->dev, PAGE_SIZE, host->sg_cpu, host->sg_dma);
 
+               clk_put(host->clk);
+
                release_resource(host->res);
 
                mmc_free_host(mmc);
index 3153e779d46a9edbd481249871d2779cf988e432..748c7706f237f3bd4077bbce3f2e5b2dd2aba196 100644 (file)
 #define MMC_RXFIFO     0x0040  /* 8 bit */
 
 #define MMC_TXFIFO     0x0044  /* 8 bit */
-
-/*
- * The base MMC clock rate
- */
-#ifdef CONFIG_PXA27x
-#define CLOCKRATE_MIN  304688
-#define CLOCKRATE_MAX  19500000
-#else
-#define CLOCKRATE_MIN  312500
-#define CLOCKRATE_MAX  20000000
-#endif
-
-#define CLOCKRATE      CLOCKRATE_MAX
-