Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-12-23 19:31:53 +00:00
Code Issues Packages Projects Releases Wiki Activity

rtc: rv3028: add clkout support

Browse Source 
rv3028 provides clkout (enabled by default). Add clkout
to clock framework source and control from device tree for
variable frequency with enable and disable functionality.

Signed-off-by: Parthiban Nallathambi <pn@denx.de>
Link: https://lore.kernel.org/r/20191018100425.1687979-1-pn@denx.de
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
This commit is contained in:
Parthiban Nallathambi 2019-10-18 12:04:25 +02:00 committed by Alexandre Belloni
parent 05df557285
commit f583c341a5
1 changed files with 146 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

146
drivers/rtc/rtc-rv3028.c
View File

@ -8,6 +8,7 @@
*
*/
#include <linux/clk-provider.h>
#include <linux/bcd.h>
#include <linux/bitops.h>
#include <linux/i2c.h>
@ -52,6 +53,11 @@
#define RV3028_STATUS_CLKF BIT(6)
#define RV3028_STATUS_EEBUSY BIT(7)
#define RV3028_CLKOUT_FD_MASK GENMASK(2, 0)
#define RV3028_CLKOUT_PORIE BIT(3)
#define RV3028_CLKOUT_CLKSY BIT(6)
#define RV3028_CLKOUT_CLKOE BIT(7)
#define RV3028_CTRL1_EERD BIT(3)
#define RV3028_CTRL1_WADA BIT(5)
@ -84,6 +90,9 @@ struct rv3028_data {
struct regmap *regmap;
struct rtc_device *rtc;
enum rv3028_type type;
#ifdef CONFIG_COMMON_CLK
struct clk_hw clkout_hw;
#endif
};
static u16 rv3028_trickle_resistors[] = {1000, 3000, 6000, 11000};
@ -581,6 +590,140 @@ restore_eerd:
return ret;
}
#ifdef CONFIG_COMMON_CLK
#define clkout_hw_to_rv3028(hw) container_of(hw, struct rv3028_data, clkout_hw)
static int clkout_rates[] = {
32768,
8192,
1024,
64,
32,
1,
};
static unsigned long rv3028_clkout_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
int clkout, ret;
struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw);
ret = regmap_read(rv3028->regmap, RV3028_CLKOUT, &clkout);
if (ret < 0)
return 0;
clkout &= RV3028_CLKOUT_FD_MASK;
return clkout_rates[clkout];
}
static long rv3028_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
int i;
for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
if (clkout_rates[i] <= rate)
return clkout_rates[i];
return 0;
}
static int rv3028_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
int i, ret;
struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw);
ret = regmap_write(rv3028->regmap, RV3028_CLKOUT, 0x0);
if (ret < 0)
return ret;
for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) {
if (clkout_rates[i] == rate) {
ret = regmap_update_bits(rv3028->regmap,
RV3028_CLKOUT,
RV3028_CLKOUT_FD_MASK, i);
if (ret < 0)
return ret;
return regmap_write(rv3028->regmap, RV3028_CLKOUT,
RV3028_CLKOUT_CLKSY | RV3028_CLKOUT_CLKOE);
}
}
return -EINVAL;
}
static int rv3028_clkout_prepare(struct clk_hw *hw)
{
struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw);
return regmap_write(rv3028->regmap, RV3028_CLKOUT,
RV3028_CLKOUT_CLKSY | RV3028_CLKOUT_CLKOE);
}
static void rv3028_clkout_unprepare(struct clk_hw *hw)
{
struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw);
regmap_write(rv3028->regmap, RV3028_CLKOUT, 0x0);
regmap_update_bits(rv3028->regmap, RV3028_STATUS,
RV3028_STATUS_CLKF, 0);
}
static int rv3028_clkout_is_prepared(struct clk_hw *hw)
{
int clkout, ret;
struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw);
ret = regmap_read(rv3028->regmap, RV3028_CLKOUT, &clkout);
if (ret < 0)
return ret;
return !!(clkout & RV3028_CLKOUT_CLKOE);
}
static const struct clk_ops rv3028_clkout_ops = {
.prepare = rv3028_clkout_prepare,
.unprepare = rv3028_clkout_unprepare,
.is_prepared = rv3028_clkout_is_prepared,
.recalc_rate = rv3028_clkout_recalc_rate,
.round_rate = rv3028_clkout_round_rate,
.set_rate = rv3028_clkout_set_rate,
};
static int rv3028_clkout_register_clk(struct rv3028_data *rv3028,
struct i2c_client *client)
{
int ret;
struct clk *clk;
struct clk_init_data init;
struct device_node *node = client->dev.of_node;
ret = regmap_update_bits(rv3028->regmap, RV3028_STATUS,
RV3028_STATUS_CLKF, 0);
if (ret < 0)
return ret;
init.name = "rv3028-clkout";
init.ops = &rv3028_clkout_ops;
init.flags = 0;
init.parent_names = NULL;
init.num_parents = 0;
rv3028->clkout_hw.init = &init;
/* optional override of the clockname */
of_property_read_string(node, "clock-output-names", &init.name);
/* register the clock */
clk = devm_clk_register(&client->dev, &rv3028->clkout_hw);
if (!IS_ERR(clk))
of_clk_add_provider(node, of_clk_src_simple_get, clk);
return 0;
}
#endif
static struct rtc_class_ops rv3028_rtc_ops = {
.read_time = rv3028_get_time,
.set_time = rv3028_set_time,
@ -708,6 +851,9 @@ static int rv3028_probe(struct i2c_client *client)
rv3028->rtc->max_user_freq = 1;
#ifdef CONFIG_COMMON_CLK
rv3028_clkout_register_clk(rv3028, client);
#endif
return 0;
}