[PATCH v2] clk: si5351: Allow user to define disabled state for every clock output
Marek Belisko
marek.belisko at gmail.com
Fri May 3 15:33:27 EST 2013
From: Sebastian Hesselbarth <sebastian.hesselbarth at gmail.com>
This patch adds platform data and DT bindings to allow to overwrite
the stored disabled state for each clock output.
Signed-off-by: Marek Belisko <marek.belisko at streamunlimited.com>
Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth at gmail.com>
---
Changes from v1->v2:
Sebastian Hesselbarth send me updated version of patch which was based
on v1. Resending with updates.
.../devicetree/bindings/clock/silabs,si5351.txt | 5 ++
drivers/clk/clk-si5351.c | 74 +++++++++++++++++++-
drivers/clk/clk-si5351.h | 1 +
include/linux/platform_data/si5351.h | 18 +++++
4 files changed, 95 insertions(+), 3 deletions(-)
diff --git a/Documentation/devicetree/bindings/clock/silabs,si5351.txt b/Documentation/devicetree/bindings/clock/silabs,si5351.txt
index cc37465..66c75b2 100644
--- a/Documentation/devicetree/bindings/clock/silabs,si5351.txt
+++ b/Documentation/devicetree/bindings/clock/silabs,si5351.txt
@@ -44,6 +44,11 @@ Optional child node properties:
- silabs,multisynth-source: source pll A(0) or B(1) of corresponding multisynth
divider.
- silabs,pll-master: boolean, multisynth can change pll frequency.
+- silabs,disable-state : clock output disable state, shall be
+ 0 = clock output is driven LOW when disabled
+ 1 = clock output is driven HIGH when disabled
+ 2 = clock output is FLOATING (HIGH-Z) when disabled
+ 3 = clock output is NEVER disabled
==Example==
diff --git a/drivers/clk/clk-si5351.c b/drivers/clk/clk-si5351.c
index 8323c31..098f28b 100644
--- a/drivers/clk/clk-si5351.c
+++ b/drivers/clk/clk-si5351.c
@@ -851,6 +851,41 @@ static int _si5351_clkout_set_drive_strength(
return 0;
}
+static int _si5351_clkout_set_disable_state(
+ struct si5351_driver_data *drvdata, int num,
+ enum si5351_disable_state state)
+{
+ u8 reg = (num < 4) ? SI5351_CLK3_0_DISABLE_STATE :
+ SI5351_CLK7_4_DISABLE_STATE;
+ u8 shift = (num < 4) ? (2 * num) : (2 * (num-4));
+ u8 mask = SI5351_CLK_DISABLE_STATE_MASK << shift;
+ u8 val;
+
+ if (num > 8)
+ return -EINVAL;
+
+ switch (state) {
+ case SI5351_DISABLE_LOW:
+ val = SI5351_CLK_DISABLE_STATE_LOW;
+ break;
+ case SI5351_DISABLE_HIGH:
+ val = SI5351_CLK_DISABLE_STATE_HIGH;
+ break;
+ case SI5351_DISABLE_FLOATING:
+ val = SI5351_CLK_DISABLE_STATE_FLOAT;
+ break;
+ case SI5351_DISABLE_NEVER:
+ val = SI5351_CLK_DISABLE_STATE_NEVER;
+ break;
+ default:
+ return 0;
+ }
+
+ si5351_set_bits(drvdata, reg, mask, val << shift);
+
+ return 0;
+}
+
static int si5351_clkout_prepare(struct clk_hw *hw)
{
struct si5351_hw_data *hwdata =
@@ -1225,6 +1260,33 @@ static int si5351_dt_parse(struct i2c_client *client)
}
}
+ if (!of_property_read_u32(child, "silabs,disable-state",
+ &val)) {
+ switch (val) {
+ case 0:
+ pdata->clkout[num].disable_state =
+ SI5351_DISABLE_LOW;
+ break;
+ case 1:
+ pdata->clkout[num].disable_state =
+ SI5351_DISABLE_HIGH;
+ break;
+ case 2:
+ pdata->clkout[num].disable_state =
+ SI5351_DISABLE_FLOATING;
+ break;
+ case 3:
+ pdata->clkout[num].disable_state =
+ SI5351_DISABLE_NEVER;
+ break;
+ default:
+ dev_err(&client->dev,
+ "invalid disable state %d for clkout %d\n",
+ val, num);
+ return -EINVAL;
+ }
+ }
+
if (!of_property_read_u32(child, "clock-frequency", &val))
pdata->clkout[num].rate = val;
@@ -1281,9 +1343,6 @@ static int si5351_i2c_probe(struct i2c_client *client,
/* Disable interrupts */
si5351_reg_write(drvdata, SI5351_INTERRUPT_MASK, 0xf0);
- /* Set disabled output drivers to drive low */
- si5351_reg_write(drvdata, SI5351_CLK3_0_DISABLE_STATE, 0x00);
- si5351_reg_write(drvdata, SI5351_CLK7_4_DISABLE_STATE, 0x00);
/* Ensure pll select is on XTAL for Si5351A/B */
if (drvdata->variant != SI5351_VARIANT_C)
si5351_set_bits(drvdata, SI5351_PLL_INPUT_SOURCE,
@@ -1327,6 +1386,15 @@ static int si5351_i2c_probe(struct i2c_client *client,
n, pdata->clkout[n].drive);
return ret;
}
+
+ ret = _si5351_clkout_set_disable_state(drvdata, n,
+ pdata->clkout[n].disable_state);
+ if (ret) {
+ dev_err(&client->dev,
+ "failed set disable state of clkout%d to %d\n",
+ n, pdata->clkout[n].disable_state);
+ return ret;
+ }
}
/* register xtal input clock gate */
diff --git a/drivers/clk/clk-si5351.h b/drivers/clk/clk-si5351.h
index af41b50..c0dbf26 100644
--- a/drivers/clk/clk-si5351.h
+++ b/drivers/clk/clk-si5351.h
@@ -81,6 +81,7 @@
#define SI5351_CLK3_0_DISABLE_STATE 24
#define SI5351_CLK7_4_DISABLE_STATE 25
+#define SI5351_CLK_DISABLE_STATE_MASK 3
#define SI5351_CLK_DISABLE_STATE_LOW 0
#define SI5351_CLK_DISABLE_STATE_HIGH 1
#define SI5351_CLK_DISABLE_STATE_FLOAT 2
diff --git a/include/linux/platform_data/si5351.h b/include/linux/platform_data/si5351.h
index 92dabca..5433439 100644
--- a/include/linux/platform_data/si5351.h
+++ b/include/linux/platform_data/si5351.h
@@ -79,6 +79,23 @@ enum si5351_drive_strength {
};
/**
+ * enum si5351_disable_state - Si5351 clock output disable state
+ * @SI5351_DISABLE_DEFAULT: default, do not change eeprom config
+ * @SI5351_DISABLE_LOW: CLKx is set to a LOW state when disabled
+ * @SI5351_DISABLE_HIGH: CLKx is set to a HIGH state when disabled
+ * @SI5351_DISABLE_FLOATING: CLKx is set to a FLOATING state when
+ * disabled
+ * @SI5351_DISABLE_NEVER: CLKx is NEVER disabled
+ */
+enum si5351_disable_state {
+ SI5351_DISABLE_DEFAULT = 0,
+ SI5351_DISABLE_LOW,
+ SI5351_DISABLE_HIGH,
+ SI5351_DISABLE_FLOATING,
+ SI5351_DISABLE_NEVER,
+};
+
+/**
* struct si5351_clkout_config - Si5351 clock output configuration
* @clkout: clkout number
* @multisynth_src: multisynth source clock
@@ -91,6 +108,7 @@ struct si5351_clkout_config {
enum si5351_multisynth_src multisynth_src;
enum si5351_clkout_src clkout_src;
enum si5351_drive_strength drive;
+ enum si5351_disable_state disable_state;
bool pll_master;
unsigned long rate;
};
--
1.7.9.5
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