Commit dd498eff authored by Denis Karpov's avatar Denis Karpov Committed by Linus Torvalds

omap_hsmmc: support for deeper power saving states

Support for multi-level dynamic power saving states in omap_hsmmc
(ENABLED->DISABLED->OFF).  In the "deepest" state (OFF) we switch off the
voltage regulators.
Signed-off-by: default avatarDenis Karpov <ext-denis.2.karpov@nokia.com>
Signed-off-by: default avatarAdrian Hunter <adrian.hunter@nokia.com>
Acked-by: default avatarMatt Fleming <matt@console-pimps.org>
Cc: Ian Molton <ian@mnementh.co.uk>
Cc: "Roberto A. Foglietta" <roberto.foglietta@gmail.com>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: Denis Karpov <ext-denis.2.karpov@nokia.com>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Philip Langdale <philipl@overt.org>
Cc: "Madhusudhan" <madhu.cr@ti.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 23d99bb9
......@@ -418,6 +418,9 @@ void __init twl4030_mmc_init(struct twl4030_hsmmc_info *controllers)
if (c->nonremovable)
mmc->slots[0].nonremovable = 1;
if (c->power_saving)
mmc->slots[0].power_saving = 1;
/* NOTE: MMC slots should have a Vcc regulator set up.
* This may be from a TWL4030-family chip, another
* controllable regulator, or a fixed supply.
......
......@@ -13,6 +13,7 @@ struct twl4030_hsmmc_info {
bool ext_clock; /* use external pin for input clock */
bool cover_only; /* No card detect - just cover switch */
bool nonremovable; /* Nonremovable e.g. eMMC */
bool power_saving; /* Try to sleep or power off when possible */
int gpio_cd; /* or -EINVAL */
int gpio_wp; /* or -EINVAL */
char *name; /* or NULL for default */
......
......@@ -86,6 +86,9 @@ struct omap_mmc_platform_data {
/* nonremovable e.g. eMMC */
unsigned nonremovable:1;
/* Try to sleep or power off when possible */
unsigned power_saving:1;
int switch_pin; /* gpio (card detect) */
int gpio_wp; /* gpio (write protect) */
......
......@@ -113,6 +113,10 @@
#define OMAP_MMC_MASTER_CLOCK 96000000
#define DRIVER_NAME "mmci-omap-hs"
/* Timeouts for entering power saving states on inactivity, msec */
#define OMAP_MMC_DISABLED_TIMEOUT 100
#define OMAP_MMC_OFF_TIMEOUT 1000
/*
* One controller can have multiple slots, like on some omap boards using
* omap.c controller driver. Luckily this is not currently done on any known
......@@ -157,6 +161,7 @@ struct mmc_omap_host {
int dbclk_enabled;
int response_busy;
int context_loss;
int dpm_state;
struct omap_mmc_platform_data *pdata;
};
......@@ -992,29 +997,6 @@ mmc_omap_prepare_data(struct mmc_omap_host *host, struct mmc_request *req)
return 0;
}
static int omap_mmc_enable(struct mmc_host *mmc)
{
struct mmc_omap_host *host = mmc_priv(mmc);
int err;
err = clk_enable(host->fclk);
if (err)
return err;
dev_dbg(mmc_dev(host->mmc), "mmc_fclk: enabled\n");
omap_mmc_restore_ctx(host);
return 0;
}
static int omap_mmc_disable(struct mmc_host *mmc, int lazy)
{
struct mmc_omap_host *host = mmc_priv(mmc);
omap_mmc_save_ctx(host);
clk_disable(host->fclk);
dev_dbg(mmc_dev(host->mmc), "mmc_fclk: disabled\n");
return 0;
}
/*
* Request function. for read/write operation
*/
......@@ -1068,6 +1050,8 @@ static void omap_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
host->power_mode = ios->power_mode;
}
/* FIXME: set registers based only on changes to ios */
con = OMAP_HSMMC_READ(host->base, CON);
switch (mmc->ios.bus_width) {
case MMC_BUS_WIDTH_8:
......@@ -1140,7 +1124,10 @@ static void omap_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
else
OMAP_HSMMC_WRITE(host->base, CON, con & ~OD);
mmc_host_lazy_disable(host->mmc);
if (host->power_mode == MMC_POWER_OFF)
mmc_host_disable(host->mmc);
else
mmc_host_lazy_disable(host->mmc);
}
static int omap_hsmmc_get_cd(struct mmc_host *mmc)
......@@ -1190,7 +1177,191 @@ static void omap_hsmmc_init(struct mmc_omap_host *host)
set_sd_bus_power(host);
}
static struct mmc_host_ops mmc_omap_ops = {
/*
* Dynamic power saving handling, FSM:
* ENABLED -> DISABLED -> OFF
* ^___________| |
* |______________________|
*
* ENABLED: mmc host is fully functional
* DISABLED: fclk is off
* OFF: fclk is off,voltage regulator is off
*
* Transition handlers return the timeout for the next state transition
* or negative error.
*/
enum {ENABLED = 0, DISABLED, OFF};
/* Handler for [ENABLED -> DISABLED] transition */
static int omap_mmc_enabled_to_disabled(struct mmc_omap_host *host)
{
omap_mmc_save_ctx(host);
clk_disable(host->fclk);
host->dpm_state = DISABLED;
dev_dbg(mmc_dev(host->mmc), "ENABLED -> DISABLED\n");
if (host->power_mode == MMC_POWER_OFF)
return 0;
return msecs_to_jiffies(OMAP_MMC_OFF_TIMEOUT);
}
/* Handler for [DISABLED -> OFF] transition */
static int omap_mmc_disabled_to_off(struct mmc_omap_host *host)
{
int new_state;
dev_dbg(mmc_dev(host->mmc), "DISABLED -> OFF\n");
if (!mmc_try_claim_host(host->mmc))
return 0;
clk_enable(host->fclk);
omap_mmc_restore_ctx(host);
if ((host->mmc->caps & MMC_CAP_NONREMOVABLE) ||
mmc_slot(host).card_detect ||
(mmc_slot(host).get_cover_state &&
mmc_slot(host).get_cover_state(host->dev, host->slot_id))) {
mmc_power_save_host(host->mmc);
new_state = OFF;
} else
new_state = DISABLED;
OMAP_HSMMC_WRITE(host->base, ISE, 0);
OMAP_HSMMC_WRITE(host->base, IE, 0);
OMAP_HSMMC_WRITE(host->base, HCTL,
OMAP_HSMMC_READ(host->base, HCTL) & ~SDBP);
clk_disable(host->fclk);
clk_disable(host->iclk);
clk_disable(host->dbclk);
host->dpm_state = new_state;
mmc_release_host(host->mmc);
return 0;
}
/* Handler for [DISABLED -> ENABLED] transition */
static int omap_mmc_disabled_to_enabled(struct mmc_omap_host *host)
{
int err;
err = clk_enable(host->fclk);
if (err < 0)
return err;
omap_mmc_restore_ctx(host);
host->dpm_state = ENABLED;
dev_dbg(mmc_dev(host->mmc), "DISABLED -> ENABLED\n");
return 0;
}
/* Handler for [OFF -> ENABLED] transition */
static int omap_mmc_off_to_enabled(struct mmc_omap_host *host)
{
clk_enable(host->fclk);
clk_enable(host->iclk);
if (clk_enable(host->dbclk))
dev_dbg(mmc_dev(host->mmc),
"Enabling debounce clk failed\n");
omap_mmc_restore_ctx(host);
omap_hsmmc_init(host);
mmc_power_restore_host(host->mmc);
host->dpm_state = ENABLED;
dev_dbg(mmc_dev(host->mmc), "OFF -> ENABLED\n");
return 0;
}
/*
* Bring MMC host to ENABLED from any other PM state.
*/
static int omap_mmc_enable(struct mmc_host *mmc)
{
struct mmc_omap_host *host = mmc_priv(mmc);
switch (host->dpm_state) {
case DISABLED:
return omap_mmc_disabled_to_enabled(host);
case OFF:
return omap_mmc_off_to_enabled(host);
default:
dev_dbg(mmc_dev(host->mmc), "UNKNOWN state\n");
return -EINVAL;
}
}
/*
* Bring MMC host in PM state (one level deeper).
*/
static int omap_mmc_disable(struct mmc_host *mmc, int lazy)
{
struct mmc_omap_host *host = mmc_priv(mmc);
switch (host->dpm_state) {
case ENABLED: {
int delay;
delay = omap_mmc_enabled_to_disabled(host);
if (lazy || delay < 0)
return delay;
return 0;
}
case DISABLED:
return omap_mmc_disabled_to_off(host);
default:
dev_dbg(mmc_dev(host->mmc), "UNKNOWN state\n");
return -EINVAL;
}
}
static int omap_mmc_enable_fclk(struct mmc_host *mmc)
{
struct mmc_omap_host *host = mmc_priv(mmc);
int err;
err = clk_enable(host->fclk);
if (err)
return err;
dev_dbg(mmc_dev(host->mmc), "mmc_fclk: enabled\n");
omap_mmc_restore_ctx(host);
return 0;
}
static int omap_mmc_disable_fclk(struct mmc_host *mmc, int lazy)
{
struct mmc_omap_host *host = mmc_priv(mmc);
omap_mmc_save_ctx(host);
clk_disable(host->fclk);
dev_dbg(mmc_dev(host->mmc), "mmc_fclk: disabled\n");
return 0;
}
static const struct mmc_host_ops mmc_omap_ops = {
.enable = omap_mmc_enable_fclk,
.disable = omap_mmc_disable_fclk,
.request = omap_mmc_request,
.set_ios = omap_mmc_set_ios,
.get_cd = omap_hsmmc_get_cd,
.get_ro = omap_hsmmc_get_ro,
/* NYET -- enable_sdio_irq */
};
static const struct mmc_host_ops mmc_omap_ps_ops = {
.enable = omap_mmc_enable,
.disable = omap_mmc_disable,
.request = omap_mmc_request,
......@@ -1214,15 +1385,22 @@ static int mmc_regs_show(struct seq_file *s, void *data)
seq_printf(s, "mmc%d:\n"
" enabled:\t%d\n"
" dpm_state:\t%d\n"
" nesting_cnt:\t%d\n"
" ctx_loss:\t%d:%d\n"
"\nregs:\n",
mmc->index, mmc->enabled ? 1 : 0, mmc->nesting_cnt,
mmc->index, mmc->enabled ? 1 : 0,
host->dpm_state, mmc->nesting_cnt,
host->context_loss, context_loss);
if (host->suspended || host->dpm_state == OFF) {
seq_printf(s, "host suspended, can't read registers\n");
return 0;
}
if (clk_enable(host->fclk) != 0) {
seq_printf(s, "can't read the regs\n");
goto err;
return 0;
}
seq_printf(s, "SYSCONFIG:\t0x%08x\n",
......@@ -1241,7 +1419,7 @@ static int mmc_regs_show(struct seq_file *s, void *data)
OMAP_HSMMC_READ(host->base, CAPA));
clk_disable(host->fclk);
err:
return 0;
}
......@@ -1323,7 +1501,11 @@ static int __init omap_mmc_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, host);
INIT_WORK(&host->mmc_carddetect_work, mmc_omap_detect);
mmc->ops = &mmc_omap_ops;
if (pdata->slots[host->slot_id].power_saving)
mmc->ops = &mmc_omap_ps_ops;
else
mmc->ops = &mmc_omap_ops;
mmc->f_min = 400000;
mmc->f_max = 52000000;
......@@ -1346,7 +1528,10 @@ static int __init omap_mmc_probe(struct platform_device *pdev)
omap_mmc_save_ctx(host);
mmc->caps |= MMC_CAP_DISABLE;
mmc_set_disable_delay(mmc, 100);
mmc_set_disable_delay(mmc, OMAP_MMC_DISABLED_TIMEOUT);
/* we start off in DISABLED state */
host->dpm_state = DISABLED;
if (mmc_host_enable(host->mmc) != 0) {
clk_put(host->iclk);
clk_put(host->fclk);
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment