@@ -23,6 +23,7 @@
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/of.h>
+#include <linux/clk.h>
#include "serial_flash_cmds.h"
@@ -297,6 +298,7 @@ struct stfsm {
struct mtd_info mtd;
struct mutex lock;
struct flash_info *info;
+ struct clk *clk;
uint32_t configuration;
uint32_t fifo_dir_delay;
@@ -1941,8 +1943,13 @@ static void stfsm_set_freq(struct stfsm *fsm, uint32_t spi_freq)
uint32_t emi_freq;
uint32_t clk_div;
- /* TODO: Make this dynamic */
- emi_freq = STFSM_DEFAULT_EMI_FREQ;
+ if (!fsm->clk) {
+ dev_warn(fsm->dev,
+ "No EMI clock available. Using default 100MHz.\n");
+
+ emi_freq = STFSM_DEFAULT_EMI_FREQ;
+ } else
+ emi_freq = clk_get_rate(fsm->clk);
/*
* Calculate clk_div - values between 2 and 128
@@ -2092,6 +2099,15 @@ static int stfsm_probe(struct platform_device *pdev)
return PTR_ERR(fsm->base);
}
+ fsm->clk = devm_clk_get(&pdev->dev, "emi_clk");
+ if (IS_ERR(fsm->clk)) {
+ dev_warn(fsm->dev, "Couldn't find EMI clock.\n");
+ fsm->clk = NULL;
+ } else if (clk_prepare_enable(fsm->clk)) {
+ dev_warn(fsm->dev, "Failed to enable EMI clock.\n");
+ fsm->clk = NULL;
+ }
+
mutex_init(&fsm->lock);
ret = stfsm_init(fsm);
@@ -2156,6 +2172,30 @@ static int stfsm_remove(struct platform_device *pdev)
return mtd_device_unregister(&fsm->mtd);
}
+#ifdef CONFIG_PM
+static int stfsmfsm_suspend(struct device *dev)
+{
+ struct stfsm *fsm = dev_get_drvdata(dev);
+
+ if (fsm->clk)
+ clk_disable_unprepare(fsm->clk);
+
+ return 0;
+}
+
+static int stfsmfsm_resume(struct device *dev)
+{
+ struct stfsm *fsm = dev_get_drvdata(dev);
+
+ if (fsm->clk)
+ clk_prepare_enable(fsm->clk);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(stfsm_pm_ops, stfsmfsm_suspend, stfsmfsm_resume);
+
static struct of_device_id stfsm_match[] = {
{ .compatible = "st,spi-fsm", },
{},
@@ -2169,6 +2209,7 @@ static struct platform_driver stfsm_driver = {
.name = "st-spi-fsm",
.owner = THIS_MODULE,
.of_match_table = stfsm_match,
+ .pm = &stfsm_pm_ops,
},
};
module_platform_driver(stfsm_driver);
ST's Common Clk Framework is now available. This patch ensures the FSM makes use of it by obtaining and enabling the EMI clock if provided. If system fails to provide the EMI clock FSM uses its original default rate. Signed-off-by: Lee Jones <lee.jones@linaro.org> --- drivers/mtd/devices/st_spi_fsm.c | 45 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 43 insertions(+), 2 deletions(-)