mtd: st_spi_fsm: Obtain and use EMI clock
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 system fails
to provide the EMI clock, we bomb out.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c
index bebc8b5..3451864 100644
--- a/drivers/mtd/devices/st_spi_fsm.c
+++ b/drivers/mtd/devices/st_spi_fsm.c
@@ -24,6 +24,7 @@
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/of.h>
+#include <linux/clk.h>
#include "serial_flash_cmds.h"
@@ -262,6 +263,7 @@
struct mtd_info mtd;
struct mutex lock;
struct flash_info *info;
+ struct clk *clk;
uint32_t configuration;
uint32_t fifo_dir_delay;
@@ -1906,8 +1908,7 @@
uint32_t emi_freq;
uint32_t clk_div;
- /* TODO: Make this dynamic */
- emi_freq = STFSM_DEFAULT_EMI_FREQ;
+ emi_freq = clk_get_rate(fsm->clk);
/*
* Calculate clk_div - values between 2 and 128
@@ -2057,6 +2058,18 @@
return PTR_ERR(fsm->base);
}
+ fsm->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(fsm->clk)) {
+ dev_err(fsm->dev, "Couldn't find EMI clock.\n");
+ return PTR_ERR(fsm->clk);
+ }
+
+ ret = clk_prepare_enable(fsm->clk);
+ if (ret) {
+ dev_err(fsm->dev, "Failed to enable EMI clock.\n");
+ return ret;
+ }
+
mutex_init(&fsm->lock);
ret = stfsm_init(fsm);
@@ -2121,6 +2134,28 @@
return mtd_device_unregister(&fsm->mtd);
}
+#ifdef CONFIG_PM_SLEEP
+static int stfsmfsm_suspend(struct device *dev)
+{
+ struct stfsm *fsm = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(fsm->clk);
+
+ return 0;
+}
+
+static int stfsmfsm_resume(struct device *dev)
+{
+ struct stfsm *fsm = dev_get_drvdata(dev);
+
+ clk_prepare_enable(fsm->clk);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(stfsm_pm_ops, stfsmfsm_suspend, stfsmfsm_resume);
+
static const struct of_device_id stfsm_match[] = {
{ .compatible = "st,spi-fsm", },
{},
@@ -2133,6 +2168,7 @@
.driver = {
.name = "st-spi-fsm",
.of_match_table = stfsm_match,
+ .pm = &stfsm_pm_ops,
},
};
module_platform_driver(stfsm_driver);