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Diffstat (limited to 'target/linux/s3c24xx/patches-2.6.26/1230-add-glamo-mci-slower-clocking-dynamic-switching.patc.patch')
-rwxr-xr-xtarget/linux/s3c24xx/patches-2.6.26/1230-add-glamo-mci-slower-clocking-dynamic-switching.patc.patch120
1 files changed, 120 insertions, 0 deletions
diff --git a/target/linux/s3c24xx/patches-2.6.26/1230-add-glamo-mci-slower-clocking-dynamic-switching.patc.patch b/target/linux/s3c24xx/patches-2.6.26/1230-add-glamo-mci-slower-clocking-dynamic-switching.patc.patch
new file mode 100755
index 0000000000..74442df10f
--- /dev/null
+++ b/target/linux/s3c24xx/patches-2.6.26/1230-add-glamo-mci-slower-clocking-dynamic-switching.patc.patch
@@ -0,0 +1,120 @@
+From 911b448d4b528c403f973f9e5aa34be94bffaf1e Mon Sep 17 00:00:00 2001
+From: Andy Green <andy@openmoko.com>
+Date: Wed, 30 Jul 2008 14:37:01 +0100
+Subject: [PATCH] add-glamo-mci-slower-clocking-dynamic-switching.patch
+
+This patch gives glamo-mci a concept of a platform-defined
+dynamic clock slowing callback. It means that platform code
+can associate some completely external state to decide if
+we run the SD clock at normal rate or a rate divided by a
+module parameter "sd_slow_ratio", which you can set on
+kernel commandline like this:
+
+glamo_mci.sd_slow_ratio=8
+
+you can also change it at runtime by
+
+echo 8 > /sys/module/glamo_mci/parameters/sd_slow_ratio
+
+If no platform callback is defined, then no slow mode
+is used. If it is defined, then the default division
+action is / 8, eg, 16MHz normal -> 2MHz slow mode.
+
+Signed-off-by: Andy Green <andy@openmoko.com>
+---
+ drivers/mfd/glamo/glamo-core.c | 2 ++
+ drivers/mfd/glamo/glamo-core.h | 2 ++
+ drivers/mfd/glamo/glamo-mci.c | 30 ++++++++++++++++++++++++++++--
+ include/linux/glamofb.h | 2 ++
+ 4 files changed, 34 insertions(+), 2 deletions(-)
+
+diff --git a/drivers/mfd/glamo/glamo-core.c b/drivers/mfd/glamo/glamo-core.c
+index cb9b056..0e7a650 100644
+--- a/drivers/mfd/glamo/glamo-core.c
++++ b/drivers/mfd/glamo/glamo-core.c
+@@ -1116,6 +1116,8 @@ static int __init glamo_probe(struct platform_device *pdev)
+ /* bring MCI specific stuff over from our MFD platform data */
+ glamo_mci_def_pdata.glamo_set_mci_power =
+ glamo->pdata->glamo_set_mci_power;
++ glamo_mci_def_pdata.glamo_mci_use_slow =
++ glamo->pdata->glamo_mci_use_slow;
+ glamo_mci_def_pdata.glamo_irq_is_wired =
+ glamo->pdata->glamo_irq_is_wired;
+ glamo_mci_def_pdata.mci_suspending =
+diff --git a/drivers/mfd/glamo/glamo-core.h b/drivers/mfd/glamo/glamo-core.h
+index c89f810..dd6f67c 100644
+--- a/drivers/mfd/glamo/glamo-core.h
++++ b/drivers/mfd/glamo/glamo-core.h
+@@ -72,6 +72,8 @@ struct glamo_mci_pdata {
+ unsigned long ocr_avail;
+ void (*glamo_set_mci_power)(unsigned char power_mode,
+ unsigned short vdd);
++ /* glamo-mci asking if it should use the slow clock to card */
++ int (*glamo_mci_use_slow)(void);
+ int (*glamo_irq_is_wired)(void);
+ void (*mci_suspending)(struct platform_device *dev);
+ int (*mci_all_dependencies_resumed)(struct platform_device *dev);
+diff --git a/drivers/mfd/glamo/glamo-mci.c b/drivers/mfd/glamo/glamo-mci.c
+index 7a2b060..d34632a 100644
+--- a/drivers/mfd/glamo/glamo-mci.c
++++ b/drivers/mfd/glamo/glamo-mci.c
+@@ -57,6 +57,23 @@ static int sd_max_clk = 50000000 / 3;
+ module_param(sd_max_clk, int, 0644);
+
+ /*
++ * Slow SD clock rate
++ *
++ * you can override this on kernel commandline using
++ *
++ * glamo_mci.sd_slow_ratio=8
++ *
++ * for example
++ *
++ * platform callback is used to decide effective clock rate, if not
++ * defined then max is used, if defined and returns nonzero, rate is
++ * divided by this factor
++ */
++
++static int sd_slow_ratio = 8;
++module_param(sd_slow_ratio, int, 0644);
++
++/*
+ * SD Signal drive strength
+ *
+ * you can override this on kernel commandline using
+@@ -554,8 +571,17 @@ static void glamo_mci_send_request(struct mmc_host *mmc)
+ cmd->opcode, cmd->arg, cmd->data, cmd->mrq->stop,
+ cmd->flags);
+
+- /* resume requested clock rate */
+- __glamo_mci_fix_card_div(host, host->clk_div);
++ /* resume requested clock rate
++ * scale it down by sd_slow_ratio if platform requests it
++ */
++ if (host->pdata->glamo_mci_use_slow)
++ if ((host->pdata->glamo_mci_use_slow)())
++ __glamo_mci_fix_card_div(host, host->clk_div *
++ sd_slow_ratio);
++ else
++ __glamo_mci_fix_card_div(host, host->clk_div);
++ else
++ __glamo_mci_fix_card_div(host, host->clk_div);
+
+ if (glamo_mci_send_command(host, cmd))
+ goto bail;
+diff --git a/include/linux/glamofb.h b/include/linux/glamofb.h
+index bb1a398..ca63355 100644
+--- a/include/linux/glamofb.h
++++ b/include/linux/glamofb.h
+@@ -31,6 +31,8 @@ struct glamofb_platform_data {
+ /* glamo mmc platform specific info */
+ void (*glamo_set_mci_power)(unsigned char power_mode,
+ unsigned short vdd);
++ /* glamo-mci asking if it should use the slow clock to card */
++ int (*glamo_mci_use_slow)(void);
+ int (*glamo_irq_is_wired)(void);
+ void (*mci_suspending)(struct platform_device *dev);
+ int (*mci_all_dependencies_resumed)(struct platform_device *dev);
+--
+1.5.6.3
+