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authorAnton Vorontsov <avorontsov@mvista.com>2010-08-10 18:01:49 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-08-11 08:59:03 -0700
commit20b1597bcf4a76ccab232fa032f5f9ad30069167 (patch)
tree37ff80d3df4d7d10a35276080f319bb340e4ea2b /drivers/mmc/host/sdhci-cns3xxx.c
parent845e3f4f06f9b1d34f39601cb6b7abfb8f40653c (diff)
downloadlinux-20b1597bcf4a76ccab232fa032f5f9ad30069167.tar.bz2
sdhci-pltfm: add support for CNS3xxx SoC devices
There's nothing special, just SoC-specific ops and quirks. Signed-off-by: Anton Vorontsov <avorontsov@mvista.com> Cc: Ben Dooks <ben@simtec.co.uk> Cc: Richard R?jfors <richard.rojfors@pelagicore.com> Cc: <linux-mmc@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/mmc/host/sdhci-cns3xxx.c')
-rw-r--r--drivers/mmc/host/sdhci-cns3xxx.c97
1 files changed, 97 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-cns3xxx.c b/drivers/mmc/host/sdhci-cns3xxx.c
new file mode 100644
index 000000000000..b7050b380d5f
--- /dev/null
+++ b/drivers/mmc/host/sdhci-cns3xxx.c
@@ -0,0 +1,97 @@
+/*
+ * SDHCI support for CNS3xxx SoC
+ *
+ * Copyright 2008 Cavium Networks
+ * Copyright 2010 MontaVista Software, LLC.
+ *
+ * Authors: Scott Shu
+ * Anton Vorontsov <avorontsov@mvista.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/mmc/host.h>
+#include <linux/sdhci-pltfm.h>
+#include <mach/cns3xxx.h>
+#include "sdhci.h"
+#include "sdhci-pltfm.h"
+
+static unsigned int sdhci_cns3xxx_get_max_clk(struct sdhci_host *host)
+{
+ return 150000000;
+}
+
+static void sdhci_cns3xxx_set_clock(struct sdhci_host *host, unsigned int clock)
+{
+ struct device *dev = mmc_dev(host->mmc);
+ int div = 1;
+ u16 clk;
+ unsigned long timeout;
+
+ if (clock == host->clock)
+ return;
+
+ sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
+
+ if (clock == 0)
+ goto out;
+
+ while (host->max_clk / div > clock) {
+ /*
+ * On CNS3xxx divider grows linearly up to 4, and then
+ * exponentially up to 256.
+ */
+ if (div < 4)
+ div += 1;
+ else if (div < 256)
+ div *= 2;
+ else
+ break;
+ }
+
+ dev_dbg(dev, "desired SD clock: %d, actual: %d\n",
+ clock, host->max_clk / div);
+
+ /* Divide by 3 is special. */
+ if (div != 3)
+ div >>= 1;
+
+ clk = div << SDHCI_DIVIDER_SHIFT;
+ clk |= SDHCI_CLOCK_INT_EN;
+ sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+ timeout = 20;
+ while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
+ & SDHCI_CLOCK_INT_STABLE)) {
+ if (timeout == 0) {
+ dev_warn(dev, "clock is unstable");
+ break;
+ }
+ timeout--;
+ mdelay(1);
+ }
+
+ clk |= SDHCI_CLOCK_CARD_EN;
+ sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+out:
+ host->clock = clock;
+}
+
+static struct sdhci_ops sdhci_cns3xxx_ops = {
+ .get_max_clock = sdhci_cns3xxx_get_max_clk,
+ .set_clock = sdhci_cns3xxx_set_clock,
+};
+
+struct sdhci_pltfm_data sdhci_cns3xxx_pdata = {
+ .ops = &sdhci_cns3xxx_ops,
+ .quirks = SDHCI_QUIRK_BROKEN_DMA |
+ SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
+ SDHCI_QUIRK_INVERTED_WRITE_PROTECT |
+ SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN |
+ SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
+ SDHCI_QUIRK_NONSTANDARD_CLOCK,
+};