sdhci-of: reorganize driver to support additional hardware

This patch breaks down sdhci-of into a core portion and a eSDHC portion,
clearing the path to easily support additional hardware using the same OF
driver.

Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 143 insertions, 0 deletions

diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c
new file mode 100644
index 0000000..d5b11a1
--- /dev/null
+++ b/drivers/mmc/host/sdhci-of-esdhc.c
@@ -0,0 +1,143 @@
+/*
+ * Freescale eSDHC controller driver.
+ *
+ * Copyright (c) 2007 Freescale Semiconductor, Inc.
+ * Copyright (c) 2009 MontaVista Software, Inc.
+ *
+ * Authors: Xiaobo Xie <X.Xie@freescale.com>
+ *	    Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ */
+
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/mmc/host.h>
+#include "sdhci-of.h"
+#include "sdhci.h"
+
+/*
+ * Ops and quirks for the Freescale eSDHC controller.
+ */
+
+#define ESDHC_DMA_SYSCTL	0x40c
+#define ESDHC_DMA_SNOOP		0x00000040
+
+#define ESDHC_SYSTEM_CONTROL	0x2c
+#define ESDHC_CLOCK_MASK	0x0000fff0
+#define ESDHC_PREDIV_SHIFT	8
+#define ESDHC_DIVIDER_SHIFT	4
+#define ESDHC_CLOCK_PEREN	0x00000004
+#define ESDHC_CLOCK_HCKEN	0x00000002
+#define ESDHC_CLOCK_IPGEN	0x00000001
+
+#define ESDHC_HOST_CONTROL_RES	0x05
+
+static u16 esdhc_readw(struct sdhci_host *host, int reg)
+{
+	u16 ret;
+
+	if (unlikely(reg == SDHCI_HOST_VERSION))
+		ret = in_be16(host->ioaddr + reg);
+	else
+		ret = sdhci_be32bs_readw(host, reg);
+	return ret;
+}
+
+static void esdhc_writew(struct sdhci_host *host, u16 val, int reg)
+{
+	if (reg == SDHCI_BLOCK_SIZE) {
+		/*
+		 * Two last DMA bits are reserved, and first one is used for
+		 * non-standard blksz of 4096 bytes that we don't support
+		 * yet. So clear the DMA boundary bits.
+		 */
+		val &= ~SDHCI_MAKE_BLKSZ(0x7, 0);
+	}
+	sdhci_be32bs_writew(host, val, reg);
+}
+
+static void esdhc_writeb(struct sdhci_host *host, u8 val, int reg)
+{
+	/* Prevent SDHCI core from writing reserved bits (e.g. HISPD). */
+	if (reg == SDHCI_HOST_CONTROL)
+		val &= ~ESDHC_HOST_CONTROL_RES;
+	sdhci_be32bs_writeb(host, val, reg);
+}
+
+static void esdhc_set_clock(struct sdhci_host *host, unsigned int clock)
+{
+	int pre_div = 2;
+	int div = 1;
+
+	clrbits32(host->ioaddr + ESDHC_SYSTEM_CONTROL, ESDHC_CLOCK_IPGEN |
+		  ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN | ESDHC_CLOCK_MASK);
+
+	if (clock == 0)
+		goto out;
+
+	while (host->max_clk / pre_div / 16 > clock && pre_div < 256)
+		pre_div *= 2;
+
+	while (host->max_clk / pre_div / div > clock && div < 16)
+		div++;
+
+	dev_dbg(mmc_dev(host->mmc), "desired SD clock: %d, actual: %d\n",
+		clock, host->max_clk / pre_div / div);
+
+	pre_div >>= 1;
+	div--;
+
+	setbits32(host->ioaddr + ESDHC_SYSTEM_CONTROL, ESDHC_CLOCK_IPGEN |
+		  ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN |
+		  div << ESDHC_DIVIDER_SHIFT | pre_div << ESDHC_PREDIV_SHIFT);
+	mdelay(100);
+out:
+	host->clock = clock;
+}
+
+static int esdhc_enable_dma(struct sdhci_host *host)
+{
+	setbits32(host->ioaddr + ESDHC_DMA_SYSCTL, ESDHC_DMA_SNOOP);
+	return 0;
+}
+
+static unsigned int esdhc_get_max_clock(struct sdhci_host *host)
+{
+	struct sdhci_of_host *of_host = sdhci_priv(host);
+
+	return of_host->clock;
+}
+
+static unsigned int esdhc_get_min_clock(struct sdhci_host *host)
+{
+	struct sdhci_of_host *of_host = sdhci_priv(host);
+
+	return of_host->clock / 256 / 16;
+}
+
+struct sdhci_of_data sdhci_esdhc = {
+	.quirks = SDHCI_QUIRK_FORCE_BLK_SZ_2048 |
+		  SDHCI_QUIRK_BROKEN_CARD_DETECTION |
+		  SDHCI_QUIRK_NO_BUSY_IRQ |
+		  SDHCI_QUIRK_NONSTANDARD_CLOCK |
+		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
+		  SDHCI_QUIRK_PIO_NEEDS_DELAY |
+		  SDHCI_QUIRK_RESTORE_IRQS_AFTER_RESET |
+		  SDHCI_QUIRK_NO_CARD_NO_RESET,
+	.ops = {
+		.readl = sdhci_be32bs_readl,
+		.readw = esdhc_readw,
+		.readb = sdhci_be32bs_readb,
+		.writel = sdhci_be32bs_writel,
+		.writew = esdhc_writew,
+		.writeb = esdhc_writeb,
+		.set_clock = esdhc_set_clock,
+		.enable_dma = esdhc_enable_dma,
+		.get_max_clock = esdhc_get_max_clock,
+		.get_min_clock = esdhc_get_min_clock,
+	},
+};