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path: root/drivers/clk/clk-si5341.c
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Diffstat (limited to 'drivers/clk/clk-si5341.c')
-rw-r--r--drivers/clk/clk-si5341.c212
1 files changed, 196 insertions, 16 deletions
diff --git a/drivers/clk/clk-si5341.c b/drivers/clk/clk-si5341.c
index 6e780c2a9e6b..3c228b018116 100644
--- a/drivers/clk/clk-si5341.c
+++ b/drivers/clk/clk-si5341.c
@@ -16,6 +16,8 @@
#include <linux/slab.h>
#include <asm/unaligned.h>
+#define SI5341_NUM_INPUTS 4
+
#define SI5341_MAX_NUM_OUTPUTS 10
#define SI5340_MAX_NUM_OUTPUTS 4
@@ -56,8 +58,8 @@ struct clk_si5341 {
struct i2c_client *i2c_client;
struct clk_si5341_synth synth[SI5341_NUM_SYNTH];
struct clk_si5341_output clk[SI5341_MAX_NUM_OUTPUTS];
- struct clk *pxtal;
- const char *pxtal_name;
+ struct clk *input_clk[SI5341_NUM_INPUTS];
+ const char *input_clk_name[SI5341_NUM_INPUTS];
const u16 *reg_output_offset;
const u16 *reg_rdiv_offset;
u64 freq_vco; /* 13500–14256 MHz */
@@ -78,10 +80,25 @@ struct clk_si5341_output_config {
#define SI5341_DEVICE_REV 0x0005
#define SI5341_STATUS 0x000C
#define SI5341_SOFT_RST 0x001C
+#define SI5341_IN_SEL 0x0021
+#define SI5341_XAXB_CFG 0x090E
+#define SI5341_IN_EN 0x0949
+#define SI5341_INX_TO_PFD_EN 0x094A
+
+/* Input selection */
+#define SI5341_IN_SEL_MASK 0x06
+#define SI5341_IN_SEL_SHIFT 1
+#define SI5341_IN_SEL_REGCTRL 0x01
+#define SI5341_INX_TO_PFD_SHIFT 4
+
+/* XTAL config bits */
+#define SI5341_XAXB_CFG_EXTCLK_EN BIT(0)
+#define SI5341_XAXB_CFG_PDNB BIT(1)
/* Input dividers (48-bit) */
#define SI5341_IN_PDIV(x) (0x0208 + ((x) * 10))
#define SI5341_IN_PSET(x) (0x020E + ((x) * 10))
+#define SI5341_PX_UPD 0x0230
/* PLL configuration */
#define SI5341_PLL_M_NUM 0x0235
@@ -120,6 +137,10 @@ struct si5341_reg_default {
u8 value;
};
+static const char * const si5341_input_clock_names[] = {
+ "in0", "in1", "in2", "xtal"
+};
+
/* Output configuration registers 0..9 are not quite logically organized */
static const u16 si5341_reg_output_offset[] = {
0x0108,
@@ -390,7 +411,112 @@ static unsigned long si5341_clk_recalc_rate(struct clk_hw *hw,
return (unsigned long)res;
}
+static int si5341_clk_get_selected_input(struct clk_si5341 *data)
+{
+ int err;
+ u32 val;
+
+ err = regmap_read(data->regmap, SI5341_IN_SEL, &val);
+ if (err < 0)
+ return err;
+
+ return (val & SI5341_IN_SEL_MASK) >> SI5341_IN_SEL_SHIFT;
+}
+
+static u8 si5341_clk_get_parent(struct clk_hw *hw)
+{
+ struct clk_si5341 *data = to_clk_si5341(hw);
+ int res = si5341_clk_get_selected_input(data);
+
+ if (res < 0)
+ return 0; /* Apparently we cannot report errors */
+
+ return res;
+}
+
+static int si5341_clk_reparent(struct clk_si5341 *data, u8 index)
+{
+ int err;
+ u8 val;
+
+ val = (index << SI5341_IN_SEL_SHIFT) & SI5341_IN_SEL_MASK;
+ /* Enable register-based input selection */
+ val |= SI5341_IN_SEL_REGCTRL;
+
+ err = regmap_update_bits(data->regmap,
+ SI5341_IN_SEL, SI5341_IN_SEL_REGCTRL | SI5341_IN_SEL_MASK, val);
+ if (err < 0)
+ return err;
+
+ if (index < 3) {
+ /* Enable input buffer for selected input */
+ err = regmap_update_bits(data->regmap,
+ SI5341_IN_EN, 0x07, BIT(index));
+ if (err < 0)
+ return err;
+
+ /* Enables the input to phase detector */
+ err = regmap_update_bits(data->regmap, SI5341_INX_TO_PFD_EN,
+ 0x7 << SI5341_INX_TO_PFD_SHIFT,
+ BIT(index + SI5341_INX_TO_PFD_SHIFT));
+ if (err < 0)
+ return err;
+
+ /* Power down XTAL oscillator and buffer */
+ err = regmap_update_bits(data->regmap, SI5341_XAXB_CFG,
+ SI5341_XAXB_CFG_PDNB, 0);
+ if (err < 0)
+ return err;
+
+ /*
+ * Set the P divider to "1". There's no explanation in the
+ * datasheet of these registers, but the clockbuilder software
+ * programs a "1" when the input is being used.
+ */
+ err = regmap_write(data->regmap, SI5341_IN_PDIV(index), 1);
+ if (err < 0)
+ return err;
+
+ err = regmap_write(data->regmap, SI5341_IN_PSET(index), 1);
+ if (err < 0)
+ return err;
+
+ /* Set update PDIV bit */
+ err = regmap_write(data->regmap, SI5341_PX_UPD, BIT(index));
+ if (err < 0)
+ return err;
+ } else {
+ /* Disable all input buffers */
+ err = regmap_update_bits(data->regmap, SI5341_IN_EN, 0x07, 0);
+ if (err < 0)
+ return err;
+
+ /* Disable input to phase detector */
+ err = regmap_update_bits(data->regmap, SI5341_INX_TO_PFD_EN,
+ 0x7 << SI5341_INX_TO_PFD_SHIFT, 0);
+ if (err < 0)
+ return err;
+
+ /* Power up XTAL oscillator and buffer */
+ err = regmap_update_bits(data->regmap, SI5341_XAXB_CFG,
+ SI5341_XAXB_CFG_PDNB, SI5341_XAXB_CFG_PDNB);
+ if (err < 0)
+ return err;
+ }
+
+ return 0;
+}
+
+static int si5341_clk_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_si5341 *data = to_clk_si5341(hw);
+
+ return si5341_clk_reparent(data, index);
+}
+
static const struct clk_ops si5341_clk_ops = {
+ .set_parent = si5341_clk_set_parent,
+ .get_parent = si5341_clk_get_parent,
.recalc_rate = si5341_clk_recalc_rate,
};
@@ -985,7 +1111,8 @@ static const struct regmap_range si5341_regmap_volatile_range[] = {
regmap_reg_range(0x000C, 0x0012), /* Status */
regmap_reg_range(0x001C, 0x001E), /* reset, finc/fdec */
regmap_reg_range(0x00E2, 0x00FE), /* NVM, interrupts, device ready */
- /* Update bits for synth config */
+ /* Update bits for P divider and synth config */
+ regmap_reg_range(SI5341_PX_UPD, SI5341_PX_UPD),
regmap_reg_range(SI5341_SYNTH_N_UPD(0), SI5341_SYNTH_N_UPD(0)),
regmap_reg_range(SI5341_SYNTH_N_UPD(1), SI5341_SYNTH_N_UPD(1)),
regmap_reg_range(SI5341_SYNTH_N_UPD(2), SI5341_SYNTH_N_UPD(2)),
@@ -1122,6 +1249,7 @@ static int si5341_initialize_pll(struct clk_si5341 *data)
struct device_node *np = data->i2c_client->dev.of_node;
u32 m_num = 0;
u32 m_den = 0;
+ int sel;
if (of_property_read_u32(np, "silabs,pll-m-num", &m_num)) {
dev_err(&data->i2c_client->dev,
@@ -1135,7 +1263,11 @@ static int si5341_initialize_pll(struct clk_si5341 *data)
if (!m_num || !m_den) {
dev_err(&data->i2c_client->dev,
"PLL configuration invalid, assume 14GHz\n");
- m_den = clk_get_rate(data->pxtal) / 10;
+ sel = si5341_clk_get_selected_input(data);
+ if (sel < 0)
+ return sel;
+
+ m_den = clk_get_rate(data->input_clk[sel]) / 10;
m_num = 1400000000;
}
@@ -1143,11 +1275,52 @@ static int si5341_initialize_pll(struct clk_si5341 *data)
SI5341_PLL_M_NUM, m_num, m_den);
}
+static int si5341_clk_select_active_input(struct clk_si5341 *data)
+{
+ int res;
+ int err;
+ int i;
+
+ res = si5341_clk_get_selected_input(data);
+ if (res < 0)
+ return res;
+
+ /* If the current register setting is invalid, pick the first input */
+ if (!data->input_clk[res]) {
+ dev_dbg(&data->i2c_client->dev,
+ "Input %d not connected, rerouting\n", res);
+ res = -ENODEV;
+ for (i = 0; i < SI5341_NUM_INPUTS; ++i) {
+ if (data->input_clk[i]) {
+ res = i;
+ break;
+ }
+ }
+ if (res < 0) {
+ dev_err(&data->i2c_client->dev,
+ "No clock input available\n");
+ return res;
+ }
+ }
+
+ /* Make sure the selected clock is also enabled and routed */
+ err = si5341_clk_reparent(data, res);
+ if (err < 0)
+ return err;
+
+ err = clk_prepare_enable(data->input_clk[res]);
+ if (err < 0)
+ return err;
+
+ return res;
+}
+
static int si5341_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct clk_si5341 *data;
struct clk_init_data init;
+ struct clk *input;
const char *root_clock_name;
const char *synth_clock_names[SI5341_NUM_SYNTH];
int err;
@@ -1161,12 +1334,16 @@ static int si5341_probe(struct i2c_client *client,
data->i2c_client = client;
- data->pxtal = devm_clk_get(&client->dev, "xtal");
- if (IS_ERR(data->pxtal)) {
- if (PTR_ERR(data->pxtal) == -EPROBE_DEFER)
- return -EPROBE_DEFER;
-
- dev_err(&client->dev, "Missing xtal clock input\n");
+ for (i = 0; i < SI5341_NUM_INPUTS; ++i) {
+ input = devm_clk_get(&client->dev, si5341_input_clock_names[i]);
+ if (IS_ERR(input)) {
+ if (PTR_ERR(input) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+ data->input_clk_name[i] = si5341_input_clock_names[i];
+ } else {
+ data->input_clk[i] = input;
+ data->input_clk_name[i] = __clk_get_name(input);
+ }
}
err = si5341_dt_parse_dt(client, config);
@@ -1188,9 +1365,6 @@ static int si5341_probe(struct i2c_client *client,
if (err < 0)
return err;
- /* "Activate" the xtal (usually a fixed clock) */
- clk_prepare_enable(data->pxtal);
-
if (of_property_read_bool(client->dev.of_node, "silabs,reprogram")) {
initialization_required = true;
} else {
@@ -1223,7 +1397,14 @@ static int si5341_probe(struct i2c_client *client,
ARRAY_SIZE(si5341_reg_defaults));
if (err < 0)
return err;
+ }
+
+ /* Input must be up and running at this point */
+ err = si5341_clk_select_active_input(data);
+ if (err < 0)
+ return err;
+ if (initialization_required) {
/* PLL configuration is required */
err = si5341_initialize_pll(data);
if (err < 0)
@@ -1231,9 +1412,8 @@ static int si5341_probe(struct i2c_client *client,
}
/* Register the PLL */
- data->pxtal_name = __clk_get_name(data->pxtal);
- init.parent_names = &data->pxtal_name;
- init.num_parents = 1; /* For now, only XTAL input supported */
+ init.parent_names = data->input_clk_name;
+ init.num_parents = SI5341_NUM_INPUTS;
init.ops = &si5341_clk_ops;
init.flags = 0;
data->hw.init = &init;