serial: max310x: Migrate to CLK API
This patch removes "frequency" parameter from MAX310X platform_data
and uses CLK API for getting clock. Clock type (XTAL/OSC) is
determined by clk name.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c
index 9e147f3..310ee55 100644
--- a/drivers/tty/serial/max310x.c
+++ b/drivers/tty/serial/max310x.c
@@ -17,6 +17,7 @@
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/bitops.h>
+#include <linux/clk.h>
#include <linux/serial_core.h>
#include <linux/serial.h>
#include <linux/tty.h>
@@ -291,6 +292,7 @@
struct max310x_devtype *devtype;
struct regmap *regmap;
struct mutex mutex;
+ struct clk *clk;
struct max310x_pdata *pdata;
int gpio_used;
#ifdef CONFIG_GPIOLIB
@@ -546,18 +548,19 @@
return 1;
}
-static int max310x_set_ref_clk(struct max310x_port *s)
+static int max310x_set_ref_clk(struct max310x_port *s, unsigned long freq,
+ bool xtal)
{
unsigned int div, clksrc, pllcfg = 0;
long besterr = -1;
- unsigned long fdiv, fmul, bestfreq = s->pdata->frequency;
+ unsigned long fdiv, fmul, bestfreq = freq;
/* First, update error without PLL */
- max310x_update_best_err(s->pdata->frequency, &besterr);
+ max310x_update_best_err(freq, &besterr);
/* Try all possible PLL dividers */
for (div = 1; (div <= 63) && besterr; div++) {
- fdiv = DIV_ROUND_CLOSEST(s->pdata->frequency, div);
+ fdiv = DIV_ROUND_CLOSEST(freq, div);
/* Try multiplier 6 */
fmul = fdiv * 6;
@@ -590,10 +593,7 @@
}
/* Configure clock source */
- if (s->pdata->driver_flags & MAX310X_EXT_CLK)
- clksrc = MAX310X_CLKSRC_EXTCLK_BIT;
- else
- clksrc = MAX310X_CLKSRC_CRYST_BIT;
+ clksrc = xtal ? MAX310X_CLKSRC_CRYST_BIT : MAX310X_CLKSRC_EXTCLK_BIT;
/* Configure PLL */
if (pllcfg) {
@@ -605,7 +605,7 @@
regmap_write(s->regmap, MAX310X_CLKSRC_REG, clksrc);
/* Wait for crystal */
- if (pllcfg && !(s->pdata->driver_flags & MAX310X_EXT_CLK))
+ if (pllcfg && xtal)
msleep(10);
return (int)bestfreq;
@@ -1078,9 +1078,11 @@
static int max310x_probe(struct device *dev, struct max310x_devtype *devtype,
struct regmap *regmap, int irq)
{
- struct max310x_port *s;
struct max310x_pdata *pdata = dev_get_platdata(dev);
- int i, ret, uartclk;
+ int i, ret, fmin, fmax, freq, uartclk;
+ struct clk *clk_osc, *clk_xtal;
+ struct max310x_port *s;
+ bool xtal = false;
if (IS_ERR(regmap))
return PTR_ERR(regmap);
@@ -1098,14 +1100,35 @@
return -ENOMEM;
}
- /* Check input frequency */
- if ((pdata->driver_flags & MAX310X_EXT_CLK) &&
- ((pdata->frequency < 500000) || (pdata->frequency > 35000000)))
- goto err_freq;
- /* Check frequency for quartz */
- if (!(pdata->driver_flags & MAX310X_EXT_CLK) &&
- ((pdata->frequency < 1000000) || (pdata->frequency > 4000000)))
- goto err_freq;
+ clk_osc = devm_clk_get(dev, "osc");
+ clk_xtal = devm_clk_get(dev, "xtal");
+ if (!IS_ERR(clk_osc)) {
+ s->clk = clk_osc;
+ fmin = 500000;
+ fmax = 35000000;
+ } else if (!IS_ERR(clk_xtal)) {
+ s->clk = clk_xtal;
+ fmin = 1000000;
+ fmax = 4000000;
+ xtal = true;
+ } else if (PTR_ERR(clk_osc) == -EPROBE_DEFER ||
+ PTR_ERR(clk_xtal) == -EPROBE_DEFER) {
+ return -EPROBE_DEFER;
+ } else {
+ dev_err(dev, "Cannot get clock\n");
+ return -EINVAL;
+ }
+
+ ret = clk_prepare_enable(s->clk);
+ if (ret)
+ return ret;
+
+ freq = clk_get_rate(s->clk);
+ /* Check frequency limits */
+ if (freq < fmin || freq > fmax) {
+ ret = -ERANGE;
+ goto out_clk;
+ }
s->pdata = pdata;
s->regmap = regmap;
@@ -1117,7 +1140,7 @@
/* Check device to ensure we are talking to what we expect */
ret = devtype->detect(dev);
if (ret)
- return ret;
+ goto out_clk;
for (i = 0; i < devtype->nr; i++) {
unsigned int offs = i << 5;
@@ -1139,7 +1162,7 @@
MAX310X_MODE1_AUTOSLEEP_BIT);
}
- uartclk = max310x_set_ref_clk(s);
+ uartclk = max310x_set_ref_clk(s, freq, xtal);
dev_dbg(dev, "Reference clock set to %i Hz\n", uartclk);
/* Register UART driver */
@@ -1151,7 +1174,7 @@
ret = uart_register_driver(&s->uart);
if (ret) {
dev_err(dev, "Registering UART driver failed\n");
- return ret;
+ goto out_clk;
}
for (i = 0; i < devtype->nr; i++) {
@@ -1208,19 +1231,19 @@
ret = devm_request_threaded_irq(dev, irq, NULL, max310x_ist,
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
dev_name(dev), s);
- if (ret) {
- dev_err(dev, "Unable to reguest IRQ %i\n", irq);
+ if (!ret)
+ return 0;
+
+ dev_err(dev, "Unable to reguest IRQ %i\n", irq);
#ifdef CONFIG_GPIOLIB
- if (s->gpio_used)
- WARN_ON(gpiochip_remove(&s->gpio));
+ if (s->gpio_used)
+ WARN_ON(gpiochip_remove(&s->gpio));
#endif
- }
+
+out_clk:
+ clk_disable_unprepare(s->clk);
return ret;
-
-err_freq:
- dev_err(dev, "Frequency parameter incorrect\n");
- return -EINVAL;
}
static int max310x_remove(struct device *dev)
@@ -1236,6 +1259,7 @@
}
uart_unregister_driver(&s->uart);
+ clk_disable_unprepare(s->clk);
#ifdef CONFIG_GPIOLIB
if (s->gpio_used)