[PATCH 1/2] ios for mmc chip select

[PATCH 1/2] ios for mmc chip select

[Pierre Ossman]

[-- Attachment #1: Type: text/plain, Size: 226 bytes --]

Adds a new ios for setting the chip select pin on MMC cards. Needed on
SD controllers which use this pin for other things and therefore cannot
have it pulled high at all times.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

[-- Attachment #2: mmc-cs.patch --]
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Index: linux/drivers/mmc/mmc.c
===================================================================
--- linux/drivers/mmc/mmc.c	(revision 151)
+++ linux/drivers/mmc/mmc.c	(working copy)
@@ -457,6 +457,11 @@
 {
 	struct mmc_command cmd;
 
+	host->ios.chip_select = MMC_CS_HIGH;
+	host->ops->set_ios(host, &host->ios);
+
+	mmc_delay(1);
+
 	cmd.opcode = MMC_GO_IDLE_STATE;
 	cmd.arg = 0;
 	cmd.flags = MMC_RSP_NONE;
@@ -464,6 +469,11 @@
 	mmc_wait_for_cmd(host, &cmd, 0);
 
 	mmc_delay(1);
+
+	host->ios.chip_select = MMC_CS_DONTCARE;
+	host->ops->set_ios(host, &host->ios);
+
+	mmc_delay(1);
 }
 
 /*
@@ -475,6 +485,7 @@
 
 	host->ios.vdd = bit;
 	host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
+	host->ios.chip_select = MMC_CS_DONTCARE;
 	host->ios.power_mode = MMC_POWER_UP;
 	host->ops->set_ios(host, &host->ios);
 
@@ -492,6 +503,7 @@
 	host->ios.clock = 0;
 	host->ios.vdd = 0;
 	host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
+	host->ios.chip_select = MMC_CS_DONTCARE;
 	host->ios.power_mode = MMC_POWER_OFF;
 	host->ops->set_ios(host, &host->ios);
 }
Index: linux/include/linux/mmc/host.h
===================================================================
--- linux/include/linux/mmc/host.h	(revision 151)
+++ linux/include/linux/mmc/host.h	(working copy)
@@ -46,6 +46,12 @@
 #define MMC_BUSMODE_OPENDRAIN	1
 #define MMC_BUSMODE_PUSHPULL	2
 
+	unsigned char	chip_select;		/* SPI chip select */
+
+#define MMC_CS_DONTCARE		0
+#define MMC_CS_HIGH		1
+#define MMC_CS_LOW		2
+
 	unsigned char	power_mode;		/* power supply mode */
 
 #define MMC_POWER_OFF		0

Re: [PATCH 1/2] ios for mmc chip select

[Russell King]

On Mon, Aug 29, 2005 at 01:13:42PM +0200, Pierre Ossman wrote:
> Adds a new ios for setting the chip select pin on MMC cards. Needed on
> SD controllers which use this pin for other things and therefore cannot
> have it pulled high at all times.

Applied, thanks.

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 Serial core