MFD,mmc: tmio_mmc: make HCLK configurable

The Toshiba parts all have a 24 MHz HCLK, but HTC ASIC3 has a 24.576 MHz HCLK
and AMD Imageon w228x's HCLK is 80 MHz. With this patch, the MFD driver
provides the HCLK frequency to tmio_mmc via mfd_cell->driver_data.

Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Acked-by: Ian Molton <ian@mnementh.co.uk>
Acked-by: Samuel Ortiz <sameo@openedhand.com>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>

drivers/mfd/t7l66xb.c

@@ -108,6 +108,10 @@ static int t7l66xb_mmc_disable(struct platform_device *mmc)
 
 /*--------------------------------------------------------------------------*/
 
+static const struct tmio_mmc_data t7166xb_mmc_data = {
+	.hclk = 24000000,
+};
+
 static const struct resource t7l66xb_mmc_resources[] = {
 	{
 		.start = 0x800,
@@ -149,6 +153,7 @@ static struct mfd_cell t7l66xb_cells[] = {
 		.name = "tmio-mmc",
 		.enable = t7l66xb_mmc_enable,
 		.disable = t7l66xb_mmc_disable,
+		.driver_data = &t7166xb_mmc_data,
 		.num_resources = ARRAY_SIZE(t7l66xb_mmc_resources),
 		.resources = t7l66xb_mmc_resources,
 	},

drivers/mfd/tc6387xb.c

@@ -75,6 +75,10 @@ static int tc6387xb_mmc_disable(struct platform_device *mmc)
 
 /*--------------------------------------------------------------------------*/
 
+const static struct tmio_mmc_data tc6387xb_mmc_data = {
+	.hclk = 24000000,
+};
+
 static struct resource tc6387xb_mmc_resources[] = {
 	{
 		.start = 0x800,
@@ -98,6 +102,7 @@ static struct mfd_cell tc6387xb_cells[] = {
 		.name = "tmio-mmc",
 		.enable = tc6387xb_mmc_enable,
 		.disable = tc6387xb_mmc_disable,
+		.driver_data = &tc6387xb_mmc_data,
 		.num_resources = ARRAY_SIZE(tc6387xb_mmc_resources),
 		.resources = tc6387xb_mmc_resources,
 	},

drivers/mfd/tc6393xb.c

@@ -136,6 +136,10 @@ static int tc6393xb_nand_enable(struct platform_device *nand)
 	return 0;
 }
 
+const static struct tmio_mmc_data tc6393xb_mmc_data = {
+	.hclk = 24000000,
+};
+
 static struct resource __devinitdata tc6393xb_nand_resources[] = {
 	{
 		.start	= 0x1000,
@@ -351,6 +355,7 @@ static struct mfd_cell __devinitdata tc6393xb_cells[] = {
 	},
 	[TC6393XB_CELL_MMC] = {
 		.name = "tmio-mmc",
+		.driver_data = &tc6393xb_mmc_data,
 		.num_resources = ARRAY_SIZE(tc6393xb_mmc_resources),
 		.resources = tc6393xb_mmc_resources,
 	},

drivers/mmc/host/tmio_mmc.c

@@ -35,23 +35,14 @@
 
 #include "tmio_mmc.h"
 
-/*
- * Fixme - documentation conflicts on what the clock values are for the
- * various dividers.
- * One document I have says that its a divisor of a 24MHz clock, another 33.
- * This probably depends on HCLK for a given platform, so we may need to
- * require HCLK be passed to us from the MFD core.
- *
- */
-
 static void tmio_mmc_set_clock(struct tmio_mmc_host *host, int new_clock)
 {
 	void __iomem *cnf = host->cnf;
 	void __iomem *ctl = host->ctl;
-	u32 clk = 0, clock;
+	u32 clk = 0, clock, f_min = host->mmc->f_min;
 
 	if (new_clock) {
-		for (clock = 46875, clk = 0x100; new_clock >= (clock<<1); ) {
+		for (clock = f_min, clk = 0x100; new_clock >= (clock<<1); ) {
 			clock <<= 1;
 			clk >>= 1;
 		}
@@ -545,6 +536,7 @@ static int tmio_mmc_resume(struct platform_device *dev)
 static int __devinit tmio_mmc_probe(struct platform_device *dev)
 {
 	struct mfd_cell	*cell = (struct mfd_cell *)dev->dev.platform_data;
+	struct tmio_mmc_data *pdata;
 	struct resource *res_ctl, *res_cnf;
 	struct tmio_mmc_host *host;
 	struct mmc_host *mmc;
@@ -560,6 +552,12 @@ static int __devinit tmio_mmc_probe(struct platform_device *dev)
 		goto out;
 	}
 
+	pdata = cell->driver_data;
+	if (!pdata || !pdata->hclk) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	mmc = mmc_alloc_host(sizeof(struct tmio_mmc_host), &dev->dev);
 	if (!mmc)
 		goto out;
@@ -578,8 +576,8 @@ static int __devinit tmio_mmc_probe(struct platform_device *dev)
 
 	mmc->ops = &tmio_mmc_ops;
 	mmc->caps = MMC_CAP_4_BIT_DATA;
-	mmc->f_min = 46875; /* 24000000 / 512 */
+	mmc->f_max = pdata->hclk;
-	mmc->f_max = 24000000;
+	mmc->f_min = mmc->f_max / 512;
 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
 
 	/* Enable the MMC/SD Control registers */

include/linux/mfd/tmio.h

@@ -18,6 +18,13 @@
 	writew((val) >> 16, (addr) + 2); \
 	} while (0)
 
+/*
+ * data for the MMC controller
+ */
+struct tmio_mmc_data {
+	unsigned int		hclk;
+};
+
 /*
  * data for the NAND controller
  */