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clk-si514, clk-si544: Implement prepare/unprepare/is_prepared operations 

This adds prepare/unprepare/is_prepared functionality to the drivers for
the SI544 and SI514 chips, allowing the clock output to be disabled when
the clock is not in use.

Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
This commit is contained in:
Mike Looijmans 2018-06-04 07:34:39 +02:00 committed by Stephen Boyd
parent ce397d215c
commit e8f127caf6
2 changed files with 74 additions and 2 deletions
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38
drivers/clk/clk-si514.c
View File

@ -74,6 +74,33 @@ static int si514_enable_output(struct clk_si514 *data, bool enable)
SI514_CONTROL_OE, enable ? SI514_CONTROL_OE : 0);
}
static int si514_prepare(struct clk_hw *hw)
{
struct clk_si514 *data = to_clk_si514(hw);
return si514_enable_output(data, true);
}
static void si514_unprepare(struct clk_hw *hw)
{
struct clk_si514 *data = to_clk_si514(hw);
si514_enable_output(data, false);
}
static int si514_is_prepared(struct clk_hw *hw)
{
struct clk_si514 *data = to_clk_si514(hw);
unsigned int val;
int err;
err = regmap_read(data->regmap, SI514_REG_CONTROL, &val);
if (err < 0)
return err;
return !!(val & SI514_CONTROL_OE);
}
/* Retrieve clock multiplier and dividers from hardware */
static int si514_get_muldiv(struct clk_si514 *data,
struct clk_si514_muldiv *settings)
@ -235,12 +262,17 @@ static int si514_set_rate(struct clk_hw *hw, unsigned long rate,
{
struct clk_si514 *data = to_clk_si514(hw);
struct clk_si514_muldiv settings;
unsigned int old_oe_state;
int err;
err = si514_calc_muldiv(&settings, rate);
if (err)
return err;
err = regmap_read(data->regmap, SI514_REG_CONTROL, &old_oe_state);
if (err)
return err;
si514_enable_output(data, false);
err = si514_set_muldiv(data, &settings);
@ -255,12 +287,16 @@ static int si514_set_rate(struct clk_hw *hw, unsigned long rate,
/* Applying a new frequency can take up to 10ms */
usleep_range(10000, 12000);
si514_enable_output(data, true);
if (old_oe_state & SI514_CONTROL_OE)
si514_enable_output(data, true);
return err;
}
static const struct clk_ops si514_clk_ops = {
.prepare = si514_prepare,
.unprepare = si514_unprepare,
.is_prepared = si514_is_prepared,
.recalc_rate = si514_recalc_rate,
.round_rate = si514_round_rate,
.set_rate = si514_set_rate,

38
drivers/clk/clk-si544.c
View File

@ -86,6 +86,33 @@ static int si544_enable_output(struct clk_si544 *data, bool enable)
SI544_OE_STATE_ODC_OE, enable ? SI544_OE_STATE_ODC_OE : 0);
}
static int si544_prepare(struct clk_hw *hw)
{
struct clk_si544 *data = to_clk_si544(hw);
return si544_enable_output(data, true);
}
static void si544_unprepare(struct clk_hw *hw)
{
struct clk_si544 *data = to_clk_si544(hw);
si544_enable_output(data, false);
}
static int si544_is_prepared(struct clk_hw *hw)
{
struct clk_si544 *data = to_clk_si544(hw);
unsigned int val;
int err;
err = regmap_read(data->regmap, SI544_REG_OE_STATE, &val);
if (err < 0)
return err;
return !!(val & SI544_OE_STATE_ODC_OE);
}
/* Retrieve clock multiplier and dividers from hardware */
static int si544_get_muldiv(struct clk_si544 *data,
struct clk_si544_muldiv *settings)
@ -273,6 +300,7 @@ static int si544_set_rate(struct clk_hw *hw, unsigned long rate,
{
struct clk_si544 *data = to_clk_si544(hw);
struct clk_si544_muldiv settings;
unsigned int old_oe_state;
int err;
if (!is_valid_frequency(data, rate))
@ -282,6 +310,10 @@ static int si544_set_rate(struct clk_hw *hw, unsigned long rate,
if (err)
return err;
err = regmap_read(data->regmap, SI544_REG_OE_STATE, &old_oe_state);
if (err)
return err;
si544_enable_output(data, false);
/* Allow FCAL for this frequency update */
@ -303,12 +335,16 @@ static int si544_set_rate(struct clk_hw *hw, unsigned long rate,
/* Applying a new frequency can take up to 10ms */
usleep_range(10000, 12000);
si544_enable_output(data, true);
if (old_oe_state & SI544_OE_STATE_ODC_OE)
si544_enable_output(data, true);
return err;
}
static const struct clk_ops si544_clk_ops = {
.prepare = si544_prepare,
.unprepare = si544_unprepare,
.is_prepared = si544_is_prepared,
.recalc_rate = si544_recalc_rate,
.round_rate = si544_round_rate,
.set_rate = si544_set_rate,