diff options
Diffstat (limited to 'target/linux/s3c24xx/patches-2.6.26/1230-add-glamo-mci-slower-clocking-dynamic-switching.patc.patch')
| -rwxr-xr-x | target/linux/s3c24xx/patches-2.6.26/1230-add-glamo-mci-slower-clocking-dynamic-switching.patc.patch | 120 |
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 + |