mmc: dw_mmc: lookup for optional biu and ciu clocks

Some platforms allow for clock gating and control of bus interface unit
clock and card interface unit clock. Add support for clock lookup of
optional biu and ciu clocks for clock gating and clock speed
determination.

Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Will Newton <will.newton@imgtec.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Thomas Abraham 2012-09-17 18:16:38 +00:00 committed by Chris Ball
parent 1c2215b7c6
commit f90a0612f0
2 changed files with 55 additions and 5 deletions

View file

@ -1960,13 +1960,42 @@ int dw_mci_probe(struct dw_mci *host)
return -ENODEV;
}
if (!host->pdata->bus_hz) {
dev_err(host->dev,
"Platform data must supply bus speed\n");
return -ENODEV;
host->biu_clk = clk_get(host->dev, "biu");
if (IS_ERR(host->biu_clk)) {
dev_dbg(host->dev, "biu clock not available\n");
} else {
ret = clk_prepare_enable(host->biu_clk);
if (ret) {
dev_err(host->dev, "failed to enable biu clock\n");
clk_put(host->biu_clk);
return ret;
}
}
host->ciu_clk = clk_get(host->dev, "ciu");
if (IS_ERR(host->ciu_clk)) {
dev_dbg(host->dev, "ciu clock not available\n");
} else {
ret = clk_prepare_enable(host->ciu_clk);
if (ret) {
dev_err(host->dev, "failed to enable ciu clock\n");
clk_put(host->ciu_clk);
goto err_clk_biu;
}
}
if (IS_ERR(host->ciu_clk))
host->bus_hz = host->pdata->bus_hz;
else
host->bus_hz = clk_get_rate(host->ciu_clk);
if (!host->bus_hz) {
dev_err(host->dev,
"Platform data must supply bus speed\n");
ret = -ENODEV;
goto err_clk_ciu;
}
host->quirks = host->pdata->quirks;
spin_lock_init(&host->lock);
@ -2116,6 +2145,17 @@ err_dmaunmap:
regulator_disable(host->vmmc);
regulator_put(host->vmmc);
}
err_clk_ciu:
if (!IS_ERR(host->ciu_clk)) {
clk_disable_unprepare(host->ciu_clk);
clk_put(host->ciu_clk);
}
err_clk_biu:
if (!IS_ERR(host->biu_clk)) {
clk_disable_unprepare(host->biu_clk);
clk_put(host->biu_clk);
}
return ret;
}
EXPORT_SYMBOL(dw_mci_probe);
@ -2149,6 +2189,12 @@ void dw_mci_remove(struct dw_mci *host)
regulator_put(host->vmmc);
}
if (!IS_ERR(host->ciu_clk))
clk_disable_unprepare(host->ciu_clk);
if (!IS_ERR(host->biu_clk))
clk_disable_unprepare(host->biu_clk);
clk_put(host->ciu_clk);
clk_put(host->biu_clk);
}
EXPORT_SYMBOL(dw_mci_remove);

View file

@ -78,6 +78,8 @@ struct mmc_data;
* @data_offset: Set the offset of DATA register according to VERID.
* @dev: Device associated with the MMC controller.
* @pdata: Platform data associated with the MMC controller.
* @biu_clk: Pointer to bus interface unit clock instance.
* @ciu_clk: Pointer to card interface unit clock instance.
* @slot: Slots sharing this MMC controller.
* @fifo_depth: depth of FIFO.
* @data_shift: log2 of FIFO item size.
@ -158,6 +160,8 @@ struct dw_mci {
u16 data_offset;
struct device *dev;
struct dw_mci_board *pdata;
struct clk *biu_clk;
struct clk *ciu_clk;
struct dw_mci_slot *slot[MAX_MCI_SLOTS];
/* FIFO push and pull */