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linux/drivers/clk/clk-si5351.c
Alvin Šipraga b2adbc9cea clk: si5351: allow PLLs to be adjusted without reset 
Introduce a new PLL reset mode flag which controls whether or not to
reset a PLL after adjusting its rate. The mode can be configured through
platform data or device tree.

Since commit 6dc669a22c ("clk: si5351: Add PLL soft reset"), the
driver unconditionally resets a PLL whenever its rate is adjusted.
The rationale was that a PLL reset was required to get three outputs
working at the same time. Before this change, the driver never reset the
PLLs.

Commit b26ff127c5 ("clk: si5351: Apply PLL soft reset before enabling
the outputs") subsequently introduced an option to reset the PLL when
enabling a clock output that sourced it. Here, the rationale was that
this is required to get a deterministic phase relationship between
multiple output clocks.

This clearly shows that it is useful to reset the PLLs in applications
where multiple clock outputs are used. However, the Si5351 also allows
for glitch-free rate adjustment of its PLLs if one avoids resetting the
PLL. In our audio application where a single Si5351 clock output is used
to supply a runtime adjustable bit clock, this unconditional PLL reset
behaviour introduces unwanted glitches in the clock output.

It would appear that the problem being solved in the former commit
may be solved by using the optional device tree property introduced in
the latter commit, obviating the need for an unconditional PLL reset
after rate adjustment. But it's not OK to break the default behaviour of
the driver, and it cannot be assumed that all device trees are using the
property introduced in the latter commit. Hence, the new behaviour is
made opt-in.

Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Rabeeh Khoury <rabeeh@solid-run.com>
Cc: Jacob Siverskog <jacob@teenage.engineering>
Cc: Sergej Sawazki <sergej@taudac.com>
Signed-off-by: Alvin Šipraga <alsi@bang-olufsen.dk>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Link: https://lore.kernel.org/r/20231124-alvin-clk-si5351-no-pll-reset-v6-3-69b82311cb90@bang-olufsen.dk
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2023-12-17 22:31:36 -08:00

1715 lines
43 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* clk-si5351.c: Skyworks / Silicon Labs Si5351A/B/C I2C Clock Generator
*
* Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
* Rabeeh Khoury <rabeeh@solid-run.com>
*
* References:
* [1] "Si5351A/B/C Data Sheet"
* https://www.skyworksinc.com/-/media/Skyworks/SL/documents/public/data-sheets/Si5351-B.pdf
* [2] "AN619: Manually Generating an Si5351 Register Map"
* https://www.skyworksinc.com/-/media/Skyworks/SL/documents/public/application-notes/AN619.pdf
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/rational.h>
#include <linux/i2c.h>
#include <linux/of.h>
#include <linux/platform_data/si5351.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <asm/div64.h>
#include "clk-si5351.h"
struct si5351_driver_data;
struct si5351_parameters {
unsigned long p1;
unsigned long p2;
unsigned long p3;
int valid;
};
struct si5351_hw_data {
struct clk_hw hw;
struct si5351_driver_data *drvdata;
struct si5351_parameters params;
unsigned char num;
};
struct si5351_driver_data {
enum si5351_variant variant;
struct i2c_client *client;
struct regmap *regmap;
struct clk *pxtal;
const char *pxtal_name;
struct clk_hw xtal;
struct clk *pclkin;
const char *pclkin_name;
struct clk_hw clkin;
struct si5351_hw_data pll[2];
struct si5351_hw_data *msynth;
struct si5351_hw_data *clkout;
size_t num_clkout;
};
static const char * const si5351_input_names[] = {
"xtal", "clkin"
};
static const char * const si5351_pll_names[] = {
"si5351_plla", "si5351_pllb", "si5351_vxco"
};
static const char * const si5351_msynth_names[] = {
"ms0", "ms1", "ms2", "ms3", "ms4", "ms5", "ms6", "ms7"
};
static const char * const si5351_clkout_names[] = {
"clk0", "clk1", "clk2", "clk3", "clk4", "clk5", "clk6", "clk7"
};
/*
* Si5351 i2c regmap
*/
static inline u8 si5351_reg_read(struct si5351_driver_data *drvdata, u8 reg)
{
u32 val;
int ret;
ret = regmap_read(drvdata->regmap, reg, &val);
if (ret) {
dev_err(&drvdata->client->dev,
"unable to read from reg%02x\n", reg);
return 0;
}
return (u8)val;
}
static inline int si5351_bulk_read(struct si5351_driver_data *drvdata,
u8 reg, u8 count, u8 *buf)
{
return regmap_bulk_read(drvdata->regmap, reg, buf, count);
}
static inline int si5351_reg_write(struct si5351_driver_data *drvdata,
u8 reg, u8 val)
{
return regmap_write(drvdata->regmap, reg, val);
}
static inline int si5351_bulk_write(struct si5351_driver_data *drvdata,
u8 reg, u8 count, const u8 *buf)
{
return regmap_raw_write(drvdata->regmap, reg, buf, count);
}
static inline int si5351_set_bits(struct si5351_driver_data *drvdata,
u8 reg, u8 mask, u8 val)
{
return regmap_update_bits(drvdata->regmap, reg, mask, val);
}
static inline u8 si5351_msynth_params_address(int num)
{
if (num > 5)
return SI5351_CLK6_PARAMETERS + (num - 6);
return SI5351_CLK0_PARAMETERS + (SI5351_PARAMETERS_LENGTH * num);
}
static void si5351_read_parameters(struct si5351_driver_data *drvdata,
u8 reg, struct si5351_parameters *params)
{
u8 buf[SI5351_PARAMETERS_LENGTH];
switch (reg) {
case SI5351_CLK6_PARAMETERS:
case SI5351_CLK7_PARAMETERS:
buf[0] = si5351_reg_read(drvdata, reg);
params->p1 = buf[0];
params->p2 = 0;
params->p3 = 1;
break;
default:
si5351_bulk_read(drvdata, reg, SI5351_PARAMETERS_LENGTH, buf);
params->p1 = ((buf[2] & 0x03) << 16) | (buf[3] << 8) | buf[4];
params->p2 = ((buf[5] & 0x0f) << 16) | (buf[6] << 8) | buf[7];
params->p3 = ((buf[5] & 0xf0) << 12) | (buf[0] << 8) | buf[1];
}
params->valid = 1;
}
static void si5351_write_parameters(struct si5351_driver_data *drvdata,
u8 reg, struct si5351_parameters *params)
{
u8 buf[SI5351_PARAMETERS_LENGTH];
switch (reg) {
case SI5351_CLK6_PARAMETERS:
case SI5351_CLK7_PARAMETERS:
buf[0] = params->p1 & 0xff;
si5351_reg_write(drvdata, reg, buf[0]);
break;
default:
buf[0] = ((params->p3 & 0x0ff00) >> 8) & 0xff;
buf[1] = params->p3 & 0xff;
/* save rdiv and divby4 */
buf[2] = si5351_reg_read(drvdata, reg + 2) & ~0x03;
buf[2] |= ((params->p1 & 0x30000) >> 16) & 0x03;
buf[3] = ((params->p1 & 0x0ff00) >> 8) & 0xff;
buf[4] = params->p1 & 0xff;
buf[5] = ((params->p3 & 0xf0000) >> 12) |
((params->p2 & 0xf0000) >> 16);
buf[6] = ((params->p2 & 0x0ff00) >> 8) & 0xff;
buf[7] = params->p2 & 0xff;
si5351_bulk_write(drvdata, reg, SI5351_PARAMETERS_LENGTH, buf);
}
}
static bool si5351_regmap_is_volatile(struct device *dev, unsigned int reg)
{
switch (reg) {
case SI5351_DEVICE_STATUS:
case SI5351_INTERRUPT_STATUS:
case SI5351_PLL_RESET:
return true;
}
return false;
}
static bool si5351_regmap_is_writeable(struct device *dev, unsigned int reg)
{
/* reserved registers */
if (reg >= 4 && reg <= 8)
return false;
if (reg >= 10 && reg <= 14)
return false;
if (reg >= 173 && reg <= 176)
return false;
if (reg >= 178 && reg <= 182)
return false;
/* read-only */
if (reg == SI5351_DEVICE_STATUS)
return false;
return true;
}
static const struct regmap_config si5351_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.cache_type = REGCACHE_MAPLE,
.max_register = 187,
.writeable_reg = si5351_regmap_is_writeable,
.volatile_reg = si5351_regmap_is_volatile,
};
/*
* Si5351 xtal clock input
*/
static int si5351_xtal_prepare(struct clk_hw *hw)
{
struct si5351_driver_data *drvdata =
container_of(hw, struct si5351_driver_data, xtal);
si5351_set_bits(drvdata, SI5351_FANOUT_ENABLE,
SI5351_XTAL_ENABLE, SI5351_XTAL_ENABLE);
return 0;
}
static void si5351_xtal_unprepare(struct clk_hw *hw)
{
struct si5351_driver_data *drvdata =
container_of(hw, struct si5351_driver_data, xtal);
si5351_set_bits(drvdata, SI5351_FANOUT_ENABLE,
SI5351_XTAL_ENABLE, 0);
}
static const struct clk_ops si5351_xtal_ops = {
.prepare = si5351_xtal_prepare,
.unprepare = si5351_xtal_unprepare,
};
/*
* Si5351 clkin clock input (Si5351C only)
*/
static int si5351_clkin_prepare(struct clk_hw *hw)
{
struct si5351_driver_data *drvdata =
container_of(hw, struct si5351_driver_data, clkin);
si5351_set_bits(drvdata, SI5351_FANOUT_ENABLE,
SI5351_CLKIN_ENABLE, SI5351_CLKIN_ENABLE);
return 0;
}
static void si5351_clkin_unprepare(struct clk_hw *hw)
{
struct si5351_driver_data *drvdata =
container_of(hw, struct si5351_driver_data, clkin);
si5351_set_bits(drvdata, SI5351_FANOUT_ENABLE,
SI5351_CLKIN_ENABLE, 0);
}
/*
* CMOS clock source constraints:
* The input frequency range of the PLL is 10Mhz to 40MHz.
* If CLKIN is >40MHz, the input divider must be used.
*/
static unsigned long si5351_clkin_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct si5351_driver_data *drvdata =
container_of(hw, struct si5351_driver_data, clkin);
unsigned long rate;
unsigned char idiv;
rate = parent_rate;
if (parent_rate > 160000000) {
idiv = SI5351_CLKIN_DIV_8;
rate /= 8;
} else if (parent_rate > 80000000) {
idiv = SI5351_CLKIN_DIV_4;
rate /= 4;
} else if (parent_rate > 40000000) {
idiv = SI5351_CLKIN_DIV_2;
rate /= 2;
} else {
idiv = SI5351_CLKIN_DIV_1;
}
si5351_set_bits(drvdata, SI5351_PLL_INPUT_SOURCE,
SI5351_CLKIN_DIV_MASK, idiv);
dev_dbg(&drvdata->client->dev, "%s - clkin div = %d, rate = %lu\n",
__func__, (1 << (idiv >> 6)), rate);
return rate;
}
static const struct clk_ops si5351_clkin_ops = {
.prepare = si5351_clkin_prepare,
.unprepare = si5351_clkin_unprepare,
.recalc_rate = si5351_clkin_recalc_rate,
};
/*
* Si5351 vxco clock input (Si5351B only)
*/
static int si5351_vxco_prepare(struct clk_hw *hw)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
dev_warn(&hwdata->drvdata->client->dev, "VXCO currently unsupported\n");
return 0;
}
static void si5351_vxco_unprepare(struct clk_hw *hw)
{
}
static unsigned long si5351_vxco_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
return 0;
}
static int si5351_vxco_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent)
{
return 0;
}
static const struct clk_ops si5351_vxco_ops = {
.prepare = si5351_vxco_prepare,
.unprepare = si5351_vxco_unprepare,
.recalc_rate = si5351_vxco_recalc_rate,
.set_rate = si5351_vxco_set_rate,
};
/*
* Si5351 pll a/b
*
* Feedback Multisynth Divider Equations [2]
*
* fVCO = fIN * (a + b/c)
*
* with 15 + 0/1048575 <= (a + b/c) <= 90 + 0/1048575 and
* fIN = fXTAL or fIN = fCLKIN/CLKIN_DIV
*
* Feedback Multisynth Register Equations
*
* (1) MSNx_P1[17:0] = 128 * a + floor(128 * b/c) - 512
* (2) MSNx_P2[19:0] = 128 * b - c * floor(128 * b/c) = (128*b) mod c
* (3) MSNx_P3[19:0] = c
*
* Transposing (2) yields: (4) floor(128 * b/c) = (128 * b / MSNx_P2)/c
*
* Using (4) on (1) yields:
* MSNx_P1 = 128 * a + (128 * b/MSNx_P2)/c - 512
* MSNx_P1 + 512 + MSNx_P2/c = 128 * a + 128 * b/c
*
* a + b/c = (MSNx_P1 + MSNx_P2/MSNx_P3 + 512)/128
* = (MSNx_P1*MSNx_P3 + MSNx_P2 + 512*MSNx_P3)/(128*MSNx_P3)
*
*/
static int _si5351_pll_reparent(struct si5351_driver_data *drvdata,
int num, enum si5351_pll_src parent)
{
u8 mask = (num == 0) ? SI5351_PLLA_SOURCE : SI5351_PLLB_SOURCE;
if (parent == SI5351_PLL_SRC_DEFAULT)
return 0;
if (num > 2)
return -EINVAL;
if (drvdata->variant != SI5351_VARIANT_C &&
parent != SI5351_PLL_SRC_XTAL)
return -EINVAL;
si5351_set_bits(drvdata, SI5351_PLL_INPUT_SOURCE, mask,
(parent == SI5351_PLL_SRC_XTAL) ? 0 : mask);
return 0;
}
static unsigned char si5351_pll_get_parent(struct clk_hw *hw)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
u8 mask = (hwdata->num == 0) ? SI5351_PLLA_SOURCE : SI5351_PLLB_SOURCE;
u8 val;
val = si5351_reg_read(hwdata->drvdata, SI5351_PLL_INPUT_SOURCE);
return (val & mask) ? 1 : 0;
}
static int si5351_pll_set_parent(struct clk_hw *hw, u8 index)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
if (hwdata->drvdata->variant != SI5351_VARIANT_C &&
index > 0)
return -EPERM;
if (index > 1)
return -EINVAL;
return _si5351_pll_reparent(hwdata->drvdata, hwdata->num,
(index == 0) ? SI5351_PLL_SRC_XTAL :
SI5351_PLL_SRC_CLKIN);
}
static unsigned long si5351_pll_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
u8 reg = (hwdata->num == 0) ? SI5351_PLLA_PARAMETERS :
SI5351_PLLB_PARAMETERS;
unsigned long long rate;
if (!hwdata->params.valid)
si5351_read_parameters(hwdata->drvdata, reg, &hwdata->params);
if (hwdata->params.p3 == 0)
return parent_rate;
/* fVCO = fIN * (P1*P3 + 512*P3 + P2)/(128*P3) */
rate = hwdata->params.p1 * hwdata->params.p3;
rate += 512 * hwdata->params.p3;
rate += hwdata->params.p2;
rate *= parent_rate;
do_div(rate, 128 * hwdata->params.p3);
dev_dbg(&hwdata->drvdata->client->dev,
"%s - %s: p1 = %lu, p2 = %lu, p3 = %lu, parent_rate = %lu, rate = %lu\n",
__func__, clk_hw_get_name(hw),
hwdata->params.p1, hwdata->params.p2, hwdata->params.p3,
parent_rate, (unsigned long)rate);
return (unsigned long)rate;
}
static int si5351_pll_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
unsigned long rate = req->rate;
unsigned long rfrac, denom, a, b, c;
unsigned long long lltmp;
if (rate < SI5351_PLL_VCO_MIN)
rate = SI5351_PLL_VCO_MIN;
if (rate > SI5351_PLL_VCO_MAX)
rate = SI5351_PLL_VCO_MAX;
/* determine integer part of feedback equation */
a = rate / req->best_parent_rate;
if (a < SI5351_PLL_A_MIN)
rate = req->best_parent_rate * SI5351_PLL_A_MIN;
if (a > SI5351_PLL_A_MAX)
rate = req->best_parent_rate * SI5351_PLL_A_MAX;
/* find best approximation for b/c = fVCO mod fIN */
denom = 1000 * 1000;
lltmp = rate % (req->best_parent_rate);
lltmp *= denom;
do_div(lltmp, req->best_parent_rate);
rfrac = (unsigned long)lltmp;
b = 0;
c = 1;
if (rfrac)
rational_best_approximation(rfrac, denom,
SI5351_PLL_B_MAX, SI5351_PLL_C_MAX, &b, &c);
/* calculate parameters */
hwdata->params.p3 = c;
hwdata->params.p2 = (128 * b) % c;
hwdata->params.p1 = 128 * a;
hwdata->params.p1 += (128 * b / c);
hwdata->params.p1 -= 512;
/* recalculate rate by fIN * (a + b/c) */
lltmp = req->best_parent_rate;
lltmp *= b;
do_div(lltmp, c);
rate = (unsigned long)lltmp;
rate += req->best_parent_rate * a;
dev_dbg(&hwdata->drvdata->client->dev,
"%s - %s: a = %lu, b = %lu, c = %lu, parent_rate = %lu, rate = %lu\n",
__func__, clk_hw_get_name(hw), a, b, c,
req->best_parent_rate, rate);
req->rate = rate;
return 0;
}
static int si5351_pll_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
struct si5351_platform_data *pdata =
hwdata->drvdata->client->dev.platform_data;
u8 reg = (hwdata->num == 0) ? SI5351_PLLA_PARAMETERS :
SI5351_PLLB_PARAMETERS;
/* write multisynth parameters */
si5351_write_parameters(hwdata->drvdata, reg, &hwdata->params);
/* plla/pllb ctrl is in clk6/clk7 ctrl registers */
si5351_set_bits(hwdata->drvdata, SI5351_CLK6_CTRL + hwdata->num,
SI5351_CLK_INTEGER_MODE,
(hwdata->params.p2 == 0) ? SI5351_CLK_INTEGER_MODE : 0);
/* Do a pll soft reset on the affected pll */
if (pdata->pll_reset[hwdata->num])
si5351_reg_write(hwdata->drvdata, SI5351_PLL_RESET,
hwdata->num == 0 ? SI5351_PLL_RESET_A :
SI5351_PLL_RESET_B);
dev_dbg(&hwdata->drvdata->client->dev,
"%s - %s: p1 = %lu, p2 = %lu, p3 = %lu, parent_rate = %lu, rate = %lu\n",
__func__, clk_hw_get_name(hw),
hwdata->params.p1, hwdata->params.p2, hwdata->params.p3,
parent_rate, rate);
return 0;
}
static const struct clk_ops si5351_pll_ops = {
.set_parent = si5351_pll_set_parent,
.get_parent = si5351_pll_get_parent,
.recalc_rate = si5351_pll_recalc_rate,
.determine_rate = si5351_pll_determine_rate,
.set_rate = si5351_pll_set_rate,
};
/*
* Si5351 multisync divider
*
* for fOUT <= 150 MHz:
*
* fOUT = (fIN * (a + b/c)) / CLKOUTDIV
*
* with 6 + 0/1048575 <= (a + b/c) <= 1800 + 0/1048575 and
* fIN = fVCO0, fVCO1
*
* Output Clock Multisynth Register Equations
*
* MSx_P1[17:0] = 128 * a + floor(128 * b/c) - 512
* MSx_P2[19:0] = 128 * b - c * floor(128 * b/c) = (128*b) mod c
* MSx_P3[19:0] = c
*
* MS[6,7] are integer (P1) divide only, P1 = divide value,
* P2 and P3 are not applicable
*
* for 150MHz < fOUT <= 160MHz:
*
* MSx_P1 = 0, MSx_P2 = 0, MSx_P3 = 1, MSx_INT = 1, MSx_DIVBY4 = 11b
*/
static int _si5351_msynth_reparent(struct si5351_driver_data *drvdata,
int num, enum si5351_multisynth_src parent)
{
if (parent == SI5351_MULTISYNTH_SRC_DEFAULT)
return 0;
if (num > 8)
return -EINVAL;
si5351_set_bits(drvdata, SI5351_CLK0_CTRL + num, SI5351_CLK_PLL_SELECT,
(parent == SI5351_MULTISYNTH_SRC_VCO0) ? 0 :
SI5351_CLK_PLL_SELECT);
return 0;
}
static unsigned char si5351_msynth_get_parent(struct clk_hw *hw)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
u8 val;
val = si5351_reg_read(hwdata->drvdata, SI5351_CLK0_CTRL + hwdata->num);
return (val & SI5351_CLK_PLL_SELECT) ? 1 : 0;
}
static int si5351_msynth_set_parent(struct clk_hw *hw, u8 index)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
return _si5351_msynth_reparent(hwdata->drvdata, hwdata->num,
(index == 0) ? SI5351_MULTISYNTH_SRC_VCO0 :
SI5351_MULTISYNTH_SRC_VCO1);
}
static unsigned long si5351_msynth_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
u8 reg = si5351_msynth_params_address(hwdata->num);
unsigned long long rate;
unsigned long m;
if (!hwdata->params.valid)
si5351_read_parameters(hwdata->drvdata, reg, &hwdata->params);
/*
* multisync0-5: fOUT = (128 * P3 * fIN) / (P1*P3 + P2 + 512*P3)
* multisync6-7: fOUT = fIN / P1
*/
rate = parent_rate;
if (hwdata->num > 5) {
m = hwdata->params.p1;
} else if (hwdata->params.p3 == 0) {
return parent_rate;
} else if ((si5351_reg_read(hwdata->drvdata, reg + 2) &
SI5351_OUTPUT_CLK_DIVBY4) == SI5351_OUTPUT_CLK_DIVBY4) {
m = 4;
} else {
rate *= 128 * hwdata->params.p3;
m = hwdata->params.p1 * hwdata->params.p3;
m += hwdata->params.p2;
m += 512 * hwdata->params.p3;
}
if (m == 0)
return 0;
do_div(rate, m);
dev_dbg(&hwdata->drvdata->client->dev,
"%s - %s: p1 = %lu, p2 = %lu, p3 = %lu, m = %lu, parent_rate = %lu, rate = %lu\n",
__func__, clk_hw_get_name(hw),
hwdata->params.p1, hwdata->params.p2, hwdata->params.p3,
m, parent_rate, (unsigned long)rate);
return (unsigned long)rate;
}
static int si5351_msynth_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
unsigned long rate = req->rate;
unsigned long long lltmp;
unsigned long a, b, c;
int divby4;
/* multisync6-7 can only handle freqencies < 150MHz */
if (hwdata->num >= 6 && rate > SI5351_MULTISYNTH67_MAX_FREQ)
rate = SI5351_MULTISYNTH67_MAX_FREQ;
/* multisync frequency is 1MHz .. 160MHz */
if (rate > SI5351_MULTISYNTH_MAX_FREQ)
rate = SI5351_MULTISYNTH_MAX_FREQ;
if (rate < SI5351_MULTISYNTH_MIN_FREQ)
rate = SI5351_MULTISYNTH_MIN_FREQ;
divby4 = 0;
if (rate > SI5351_MULTISYNTH_DIVBY4_FREQ)
divby4 = 1;
/* multisync can set pll */
if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) {
/*
* find largest integer divider for max
* vco frequency and given target rate
*/
if (divby4 == 0) {
lltmp = SI5351_PLL_VCO_MAX;
do_div(lltmp, rate);
a = (unsigned long)lltmp;
} else
a = 4;
b = 0;
c = 1;
req->best_parent_rate = a * rate;
} else if (hwdata->num >= 6) {
/* determine the closest integer divider */
a = DIV_ROUND_CLOSEST(req->best_parent_rate, rate);
if (a < SI5351_MULTISYNTH_A_MIN)
a = SI5351_MULTISYNTH_A_MIN;
if (a > SI5351_MULTISYNTH67_A_MAX)
a = SI5351_MULTISYNTH67_A_MAX;
b = 0;
c = 1;
} else {
unsigned long rfrac, denom;
/* disable divby4 */
if (divby4) {
rate = SI5351_MULTISYNTH_DIVBY4_FREQ;
divby4 = 0;
}
/* determine integer part of divider equation */
a = req->best_parent_rate / rate;
if (a < SI5351_MULTISYNTH_A_MIN)
a = SI5351_MULTISYNTH_A_MIN;
if (a > SI5351_MULTISYNTH_A_MAX)
a = SI5351_MULTISYNTH_A_MAX;
/* find best approximation for b/c = fVCO mod fOUT */
denom = 1000 * 1000;
lltmp = req->best_parent_rate % rate;
lltmp *= denom;
do_div(lltmp, rate);
rfrac = (unsigned long)lltmp;
b = 0;
c = 1;
if (rfrac)
rational_best_approximation(rfrac, denom,
SI5351_MULTISYNTH_B_MAX, SI5351_MULTISYNTH_C_MAX,
&b, &c);
}
/* recalculate rate by fOUT = fIN / (a + b/c) */
lltmp = req->best_parent_rate;
lltmp *= c;
do_div(lltmp, a * c + b);
rate = (unsigned long)lltmp;
/* calculate parameters */
if (divby4) {
hwdata->params.p3 = 1;
hwdata->params.p2 = 0;
hwdata->params.p1 = 0;
} else if (hwdata->num >= 6) {
hwdata->params.p3 = 0;
hwdata->params.p2 = 0;
hwdata->params.p1 = a;
} else {
hwdata->params.p3 = c;
hwdata->params.p2 = (128 * b) % c;
hwdata->params.p1 = 128 * a;
hwdata->params.p1 += (128 * b / c);
hwdata->params.p1 -= 512;
}
dev_dbg(&hwdata->drvdata->client->dev,
"%s - %s: a = %lu, b = %lu, c = %lu, divby4 = %d, parent_rate = %lu, rate = %lu\n",
__func__, clk_hw_get_name(hw), a, b, c, divby4,
req->best_parent_rate, rate);
req->rate = rate;
return 0;
}
static int si5351_msynth_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
u8 reg = si5351_msynth_params_address(hwdata->num);
int divby4 = 0;
/* write multisynth parameters */
si5351_write_parameters(hwdata->drvdata, reg, &hwdata->params);
if (rate > SI5351_MULTISYNTH_DIVBY4_FREQ)
divby4 = 1;
/* enable/disable integer mode and divby4 on multisynth0-5 */
if (hwdata->num < 6) {
si5351_set_bits(hwdata->drvdata, reg + 2,
SI5351_OUTPUT_CLK_DIVBY4,
(divby4) ? SI5351_OUTPUT_CLK_DIVBY4 : 0);
si5351_set_bits(hwdata->drvdata, SI5351_CLK0_CTRL + hwdata->num,
SI5351_CLK_INTEGER_MODE,
(hwdata->params.p2 == 0) ? SI5351_CLK_INTEGER_MODE : 0);
}
dev_dbg(&hwdata->drvdata->client->dev,
"%s - %s: p1 = %lu, p2 = %lu, p3 = %lu, divby4 = %d, parent_rate = %lu, rate = %lu\n",
__func__, clk_hw_get_name(hw),
hwdata->params.p1, hwdata->params.p2, hwdata->params.p3,
divby4, parent_rate, rate);
return 0;
}
static const struct clk_ops si5351_msynth_ops = {
.set_parent = si5351_msynth_set_parent,
.get_parent = si5351_msynth_get_parent,
.recalc_rate = si5351_msynth_recalc_rate,
.determine_rate = si5351_msynth_determine_rate,
.set_rate = si5351_msynth_set_rate,
};
/*
* Si5351 clkout divider
*/
static int _si5351_clkout_reparent(struct si5351_driver_data *drvdata,
int num, enum si5351_clkout_src parent)
{
u8 val;
if (num > 8)
return -EINVAL;
switch (parent) {
case SI5351_CLKOUT_SRC_MSYNTH_N:
val = SI5351_CLK_INPUT_MULTISYNTH_N;
break;
case SI5351_CLKOUT_SRC_MSYNTH_0_4:
/* clk0/clk4 can only connect to its own multisync */
if (num == 0 || num == 4)
val = SI5351_CLK_INPUT_MULTISYNTH_N;
else
val = SI5351_CLK_INPUT_MULTISYNTH_0_4;
break;
case SI5351_CLKOUT_SRC_XTAL:
val = SI5351_CLK_INPUT_XTAL;
break;
case SI5351_CLKOUT_SRC_CLKIN:
if (drvdata->variant != SI5351_VARIANT_C)
return -EINVAL;
val = SI5351_CLK_INPUT_CLKIN;
break;
default:
return 0;
}
si5351_set_bits(drvdata, SI5351_CLK0_CTRL + num,
SI5351_CLK_INPUT_MASK, val);
return 0;
}
static int _si5351_clkout_set_drive_strength(
struct si5351_driver_data *drvdata, int num,
enum si5351_drive_strength drive)
{
u8 mask;
if (num > 8)
return -EINVAL;
switch (drive) {
case SI5351_DRIVE_2MA:
mask = SI5351_CLK_DRIVE_STRENGTH_2MA;
break;
case SI5351_DRIVE_4MA:
mask = SI5351_CLK_DRIVE_STRENGTH_4MA;
break;
case SI5351_DRIVE_6MA:
mask = SI5351_CLK_DRIVE_STRENGTH_6MA;
break;
case SI5351_DRIVE_8MA:
mask = SI5351_CLK_DRIVE_STRENGTH_8MA;
break;
default:
return 0;
}
si5351_set_bits(drvdata, SI5351_CLK0_CTRL + num,
SI5351_CLK_DRIVE_STRENGTH_MASK, mask);
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 void _si5351_clkout_reset_pll(struct si5351_driver_data *drvdata, int num)
{
u8 val = si5351_reg_read(drvdata, SI5351_CLK0_CTRL + num);
u8 mask = val & SI5351_CLK_PLL_SELECT ? SI5351_PLL_RESET_B :
SI5351_PLL_RESET_A;
unsigned int v;
int err;
switch (val & SI5351_CLK_INPUT_MASK) {
case SI5351_CLK_INPUT_XTAL:
case SI5351_CLK_INPUT_CLKIN:
return; /* pll not used, no need to reset */
}
si5351_reg_write(drvdata, SI5351_PLL_RESET, mask);
err = regmap_read_poll_timeout(drvdata->regmap, SI5351_PLL_RESET, v,
!(v & mask), 0, 20000);
if (err < 0)
dev_err(&drvdata->client->dev, "Reset bit didn't clear\n");
dev_dbg(&drvdata->client->dev, "%s - %s: pll = %d\n",
__func__, clk_hw_get_name(&drvdata->clkout[num].hw),
(val & SI5351_CLK_PLL_SELECT) ? 1 : 0);
}
static int si5351_clkout_prepare(struct clk_hw *hw)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
struct si5351_platform_data *pdata =
hwdata->drvdata->client->dev.platform_data;
si5351_set_bits(hwdata->drvdata, SI5351_CLK0_CTRL + hwdata->num,
SI5351_CLK_POWERDOWN, 0);
/*
* Do a pll soft reset on the parent pll -- needed to get a
* deterministic phase relationship between the output clocks.
*/
if (pdata->clkout[hwdata->num].pll_reset)
_si5351_clkout_reset_pll(hwdata->drvdata, hwdata->num);
si5351_set_bits(hwdata->drvdata, SI5351_OUTPUT_ENABLE_CTRL,
(1 << hwdata->num), 0);
return 0;
}
static void si5351_clkout_unprepare(struct clk_hw *hw)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
si5351_set_bits(hwdata->drvdata, SI5351_CLK0_CTRL + hwdata->num,
SI5351_CLK_POWERDOWN, SI5351_CLK_POWERDOWN);
si5351_set_bits(hwdata->drvdata, SI5351_OUTPUT_ENABLE_CTRL,
(1 << hwdata->num), (1 << hwdata->num));
}
static u8 si5351_clkout_get_parent(struct clk_hw *hw)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
int index = 0;
unsigned char val;
val = si5351_reg_read(hwdata->drvdata, SI5351_CLK0_CTRL + hwdata->num);
switch (val & SI5351_CLK_INPUT_MASK) {
case SI5351_CLK_INPUT_MULTISYNTH_N:
index = 0;
break;
case SI5351_CLK_INPUT_MULTISYNTH_0_4:
index = 1;
break;
case SI5351_CLK_INPUT_XTAL:
index = 2;
break;
case SI5351_CLK_INPUT_CLKIN:
index = 3;
break;
}
return index;
}
static int si5351_clkout_set_parent(struct clk_hw *hw, u8 index)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
enum si5351_clkout_src parent = SI5351_CLKOUT_SRC_DEFAULT;
switch (index) {
case 0:
parent = SI5351_CLKOUT_SRC_MSYNTH_N;
break;
case 1:
parent = SI5351_CLKOUT_SRC_MSYNTH_0_4;
break;
case 2:
parent = SI5351_CLKOUT_SRC_XTAL;
break;
case 3:
parent = SI5351_CLKOUT_SRC_CLKIN;
break;
}
return _si5351_clkout_reparent(hwdata->drvdata, hwdata->num, parent);
}
static unsigned long si5351_clkout_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
unsigned char reg;
unsigned char rdiv;
if (hwdata->num <= 5)
reg = si5351_msynth_params_address(hwdata->num) + 2;
else
reg = SI5351_CLK6_7_OUTPUT_DIVIDER;
rdiv = si5351_reg_read(hwdata->drvdata, reg);
if (hwdata->num == 6) {
rdiv &= SI5351_OUTPUT_CLK6_DIV_MASK;
} else {
rdiv &= SI5351_OUTPUT_CLK_DIV_MASK;
rdiv >>= SI5351_OUTPUT_CLK_DIV_SHIFT;
}
return parent_rate >> rdiv;
}
static int si5351_clkout_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
unsigned long rate = req->rate;
unsigned char rdiv;
/* clkout6/7 can only handle output freqencies < 150MHz */
if (hwdata->num >= 6 && rate > SI5351_CLKOUT67_MAX_FREQ)
rate = SI5351_CLKOUT67_MAX_FREQ;
/* clkout freqency is 8kHz - 160MHz */
if (rate > SI5351_CLKOUT_MAX_FREQ)
rate = SI5351_CLKOUT_MAX_FREQ;
if (rate < SI5351_CLKOUT_MIN_FREQ)
rate = SI5351_CLKOUT_MIN_FREQ;
/* request frequency if multisync master */
if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) {
/* use r divider for frequencies below 1MHz */
rdiv = SI5351_OUTPUT_CLK_DIV_1;
while (rate < SI5351_MULTISYNTH_MIN_FREQ &&
rdiv < SI5351_OUTPUT_CLK_DIV_128) {
rdiv += 1;
rate *= 2;
}
req->best_parent_rate = rate;
} else {
unsigned long new_rate, new_err, err;
/* round to closed rdiv */
rdiv = SI5351_OUTPUT_CLK_DIV_1;
new_rate = req->best_parent_rate;
err = abs(new_rate - rate);
do {
new_rate >>= 1;
new_err = abs(new_rate - rate);
if (new_err > err || rdiv == SI5351_OUTPUT_CLK_DIV_128)
break;
rdiv++;
err = new_err;
} while (1);
}
rate = req->best_parent_rate >> rdiv;
dev_dbg(&hwdata->drvdata->client->dev,
"%s - %s: rdiv = %u, parent_rate = %lu, rate = %lu\n",
__func__, clk_hw_get_name(hw), (1 << rdiv),
req->best_parent_rate, rate);
req->rate = rate;
return 0;
}
static int si5351_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct si5351_hw_data *hwdata =
container_of(hw, struct si5351_hw_data, hw);
unsigned long new_rate, new_err, err;
unsigned char rdiv;
/* round to closed rdiv */
rdiv = SI5351_OUTPUT_CLK_DIV_1;
new_rate = parent_rate;
err = abs(new_rate - rate);
do {
new_rate >>= 1;
new_err = abs(new_rate - rate);
if (new_err > err || rdiv == SI5351_OUTPUT_CLK_DIV_128)
break;
rdiv++;
err = new_err;
} while (1);
/* write output divider */
switch (hwdata->num) {
case 6:
si5351_set_bits(hwdata->drvdata, SI5351_CLK6_7_OUTPUT_DIVIDER,
SI5351_OUTPUT_CLK6_DIV_MASK, rdiv);
break;
case 7:
si5351_set_bits(hwdata->drvdata, SI5351_CLK6_7_OUTPUT_DIVIDER,
SI5351_OUTPUT_CLK_DIV_MASK,
rdiv << SI5351_OUTPUT_CLK_DIV_SHIFT);
break;
default:
si5351_set_bits(hwdata->drvdata,
si5351_msynth_params_address(hwdata->num) + 2,
SI5351_OUTPUT_CLK_DIV_MASK,
rdiv << SI5351_OUTPUT_CLK_DIV_SHIFT);
}
/* powerup clkout */
si5351_set_bits(hwdata->drvdata, SI5351_CLK0_CTRL + hwdata->num,
SI5351_CLK_POWERDOWN, 0);
dev_dbg(&hwdata->drvdata->client->dev,
"%s - %s: rdiv = %u, parent_rate = %lu, rate = %lu\n",
__func__, clk_hw_get_name(hw), (1 << rdiv),
parent_rate, rate);
return 0;
}
static const struct clk_ops si5351_clkout_ops = {
.prepare = si5351_clkout_prepare,
.unprepare = si5351_clkout_unprepare,
.set_parent = si5351_clkout_set_parent,
.get_parent = si5351_clkout_get_parent,
.recalc_rate = si5351_clkout_recalc_rate,
.determine_rate = si5351_clkout_determine_rate,
.set_rate = si5351_clkout_set_rate,
};
/*
* Si5351 i2c probe and DT
*/
#ifdef CONFIG_OF
static const struct of_device_id si5351_dt_ids[] = {
{ .compatible = "silabs,si5351a", .data = (void *)SI5351_VARIANT_A, },
{ .compatible = "silabs,si5351a-msop",
.data = (void *)SI5351_VARIANT_A3, },
{ .compatible = "silabs,si5351b", .data = (void *)SI5351_VARIANT_B, },
{ .compatible = "silabs,si5351c", .data = (void *)SI5351_VARIANT_C, },
{ }
};
MODULE_DEVICE_TABLE(of, si5351_dt_ids);
static int si5351_dt_parse(struct i2c_client *client,
enum si5351_variant variant)
{
struct device_node *child, *np = client->dev.of_node;
struct si5351_platform_data *pdata;
struct property *prop;
const __be32 *p;
int num = 0;
u32 val;
if (np == NULL)
return 0;
pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return -ENOMEM;
/*
* property silabs,pll-source : <num src>, [<..>]
* allow to selectively set pll source
*/
of_property_for_each_u32(np, "silabs,pll-source", prop, p, num) {
if (num >= 2) {
dev_err(&client->dev,
"invalid pll %d on pll-source prop\n", num);
return -EINVAL;
}
p = of_prop_next_u32(prop, p, &val);
if (!p) {
dev_err(&client->dev,
"missing pll-source for pll %d\n", num);
return -EINVAL;
}
switch (val) {
case 0:
pdata->pll_src[num] = SI5351_PLL_SRC_XTAL;
break;
case 1:
if (variant != SI5351_VARIANT_C) {
dev_err(&client->dev,
"invalid parent %d for pll %d\n",
val, num);
return -EINVAL;
}
pdata->pll_src[num] = SI5351_PLL_SRC_CLKIN;
break;
default:
dev_err(&client->dev,
"invalid parent %d for pll %d\n", val, num);
return -EINVAL;
}
}
/*
* Parse PLL reset mode. For compatibility with older device trees, the
* default is to always reset a PLL after setting its rate.
*/
pdata->pll_reset[0] = true;
pdata->pll_reset[1] = true;
of_property_for_each_u32(np, "silabs,pll-reset-mode", prop, p, num) {
if (num >= 2) {
dev_err(&client->dev,
"invalid pll %d on pll-reset-mode prop\n", num);
return -EINVAL;
}
p = of_prop_next_u32(prop, p, &val);
if (!p) {
dev_err(&client->dev,
"missing pll-reset-mode for pll %d\n", num);
return -EINVAL;
}
switch (val) {
case 0:
/* Reset PLL whenever its rate is adjusted */
pdata->pll_reset[num] = true;
break;
case 1:
/* Don't reset PLL whenever its rate is adjusted */
pdata->pll_reset[num] = false;
break;
default:
dev_err(&client->dev,
"invalid pll-reset-mode %d for pll %d\n", val,
num);
return -EINVAL;
}
}
/* per clkout properties */
for_each_child_of_node(np, child) {
if (of_property_read_u32(child, "reg", &num)) {
dev_err(&client->dev, "missing reg property of %pOFn\n",
child);
goto put_child;
}
if (num >= 8 ||
(variant == SI5351_VARIANT_A3 && num >= 3)) {
dev_err(&client->dev, "invalid clkout %d\n", num);
goto put_child;
}
if (!of_property_read_u32(child, "silabs,multisynth-source",
&val)) {
switch (val) {
case 0:
pdata->clkout[num].multisynth_src =
SI5351_MULTISYNTH_SRC_VCO0;
break;
case 1:
pdata->clkout[num].multisynth_src =
SI5351_MULTISYNTH_SRC_VCO1;
break;
default:
dev_err(&client->dev,
"invalid parent %d for multisynth %d\n",
val, num);
goto put_child;
}
}
if (!of_property_read_u32(child, "silabs,clock-source", &val)) {
switch (val) {
case 0:
pdata->clkout[num].clkout_src =
SI5351_CLKOUT_SRC_MSYNTH_N;
break;
case 1:
pdata->clkout[num].clkout_src =
SI5351_CLKOUT_SRC_MSYNTH_0_4;
break;
case 2:
pdata->clkout[num].clkout_src =
SI5351_CLKOUT_SRC_XTAL;
break;
case 3:
if (variant != SI5351_VARIANT_C) {
dev_err(&client->dev,
"invalid parent %d for clkout %d\n",
val, num);
goto put_child;
}
pdata->clkout[num].clkout_src =
SI5351_CLKOUT_SRC_CLKIN;
break;
default:
dev_err(&client->dev,
"invalid parent %d for clkout %d\n",
val, num);
goto put_child;
}
}
if (!of_property_read_u32(child, "silabs,drive-strength",
&val)) {
switch (val) {
case SI5351_DRIVE_2MA:
case SI5351_DRIVE_4MA:
case SI5351_DRIVE_6MA:
case SI5351_DRIVE_8MA:
pdata->clkout[num].drive = val;
break;
default:
dev_err(&client->dev,
"invalid drive strength %d for clkout %d\n",
val, num);
goto put_child;
}
}
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);
goto put_child;
}
}
if (!of_property_read_u32(child, "clock-frequency", &val))
pdata->clkout[num].rate = val;
pdata->clkout[num].pll_master =
of_property_read_bool(child, "silabs,pll-master");
pdata->clkout[num].pll_reset =
of_property_read_bool(child, "silabs,pll-reset");
}
client->dev.platform_data = pdata;
return 0;
put_child:
of_node_put(child);
return -EINVAL;
}
static struct clk_hw *
si53351_of_clk_get(struct of_phandle_args *clkspec, void *data)
{
struct si5351_driver_data *drvdata = data;
unsigned int idx = clkspec->args[0];
if (idx >= drvdata->num_clkout) {
pr_err("%s: invalid index %u\n", __func__, idx);
return ERR_PTR(-EINVAL);
}
return &drvdata->clkout[idx].hw;
}
#else
static int si5351_dt_parse(struct i2c_client *client, enum si5351_variant variant)
{
return 0;
}
static struct clk_hw *
si53351_of_clk_get(struct of_phandle_args *clkspec, void *data)
{
return NULL;
}
#endif /* CONFIG_OF */
static const struct i2c_device_id si5351_i2c_ids[] = {
{ "si5351a", SI5351_VARIANT_A },
{ "si5351a-msop", SI5351_VARIANT_A3 },
{ "si5351b", SI5351_VARIANT_B },
{ "si5351c", SI5351_VARIANT_C },
{ }
};
MODULE_DEVICE_TABLE(i2c, si5351_i2c_ids);
static int si5351_i2c_probe(struct i2c_client *client)
{
enum si5351_variant variant;
struct si5351_platform_data *pdata;
struct si5351_driver_data *drvdata;
struct clk_init_data init;
const char *parent_names[4];
u8 num_parents, num_clocks;
int ret, n;
variant = (enum si5351_variant)(uintptr_t)i2c_get_match_data(client);
ret = si5351_dt_parse(client, variant);
if (ret)
return ret;
pdata = client->dev.platform_data;
if (!pdata)
return -EINVAL;
drvdata = devm_kzalloc(&client->dev, sizeof(*drvdata), GFP_KERNEL);
if (!drvdata)
return -ENOMEM;
i2c_set_clientdata(client, drvdata);
drvdata->client = client;
drvdata->variant = variant;
drvdata->pxtal = devm_clk_get(&client->dev, "xtal");
drvdata->pclkin = devm_clk_get(&client->dev, "clkin");
if (PTR_ERR(drvdata->pxtal) == -EPROBE_DEFER ||
PTR_ERR(drvdata->pclkin) == -EPROBE_DEFER)
return -EPROBE_DEFER;
/*
* Check for valid parent clock: VARIANT_A and VARIANT_B need XTAL,
* VARIANT_C can have CLKIN instead.
*/
if (IS_ERR(drvdata->pxtal) &&
(drvdata->variant != SI5351_VARIANT_C || IS_ERR(drvdata->pclkin))) {
dev_err(&client->dev, "missing parent clock\n");
return -EINVAL;
}
drvdata->regmap = devm_regmap_init_i2c(client, &si5351_regmap_config);
if (IS_ERR(drvdata->regmap)) {
dev_err(&client->dev, "failed to allocate register map\n");
return PTR_ERR(drvdata->regmap);
}
/* Disable interrupts */
si5351_reg_write(drvdata, SI5351_INTERRUPT_MASK, 0xf0);
/* Ensure pll select is on XTAL for Si5351A/B */
if (drvdata->variant != SI5351_VARIANT_C)
si5351_set_bits(drvdata, SI5351_PLL_INPUT_SOURCE,
SI5351_PLLA_SOURCE | SI5351_PLLB_SOURCE, 0);
/* setup clock configuration */
for (n = 0; n < 2; n++) {
ret = _si5351_pll_reparent(drvdata, n, pdata->pll_src[n]);
if (ret) {
dev_err(&client->dev,
"failed to reparent pll %d to %d\n",
n, pdata->pll_src[n]);
return ret;
}
}
for (n = 0; n < 8; n++) {
ret = _si5351_msynth_reparent(drvdata, n,
pdata->clkout[n].multisynth_src);
if (ret) {
dev_err(&client->dev,
"failed to reparent multisynth %d to %d\n",
n, pdata->clkout[n].multisynth_src);
return ret;
}
ret = _si5351_clkout_reparent(drvdata, n,
pdata->clkout[n].clkout_src);
if (ret) {
dev_err(&client->dev,
"failed to reparent clkout %d to %d\n",
n, pdata->clkout[n].clkout_src);
return ret;
}
ret = _si5351_clkout_set_drive_strength(drvdata, n,
pdata->clkout[n].drive);
if (ret) {
dev_err(&client->dev,
"failed set drive strength of clkout%d to %d\n",
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 */
memset(&init, 0, sizeof(init));
init.name = si5351_input_names[0];
init.ops = &si5351_xtal_ops;
init.flags = 0;
if (!IS_ERR(drvdata->pxtal)) {
drvdata->pxtal_name = __clk_get_name(drvdata->pxtal);
init.parent_names = &drvdata->pxtal_name;
init.num_parents = 1;
}
drvdata->xtal.init = &init;
ret = devm_clk_hw_register(&client->dev, &drvdata->xtal);
if (ret) {
dev_err(&client->dev, "unable to register %s\n", init.name);
return ret;
}
/* register clkin input clock gate */
if (drvdata->variant == SI5351_VARIANT_C) {
memset(&init, 0, sizeof(init));
init.name = si5351_input_names[1];
init.ops = &si5351_clkin_ops;
if (!IS_ERR(drvdata->pclkin)) {
drvdata->pclkin_name = __clk_get_name(drvdata->pclkin);
init.parent_names = &drvdata->pclkin_name;
init.num_parents = 1;
}
drvdata->clkin.init = &init;
ret = devm_clk_hw_register(&client->dev, &drvdata->clkin);
if (ret) {
dev_err(&client->dev, "unable to register %s\n",
init.name);
return ret;
}
}
/* Si5351C allows to mux either xtal or clkin to PLL input */
num_parents = (drvdata->variant == SI5351_VARIANT_C) ? 2 : 1;
parent_names[0] = si5351_input_names[0];
parent_names[1] = si5351_input_names[1];
/* register PLLA */
drvdata->pll[0].num = 0;
drvdata->pll[0].drvdata = drvdata;
drvdata->pll[0].hw.init = &init;
memset(&init, 0, sizeof(init));
init.name = si5351_pll_names[0];
init.ops = &si5351_pll_ops;
init.flags = 0;
init.parent_names = parent_names;
init.num_parents = num_parents;
ret = devm_clk_hw_register(&client->dev, &drvdata->pll[0].hw);
if (ret) {
dev_err(&client->dev, "unable to register %s\n", init.name);
return ret;
}
/* register PLLB or VXCO (Si5351B) */
drvdata->pll[1].num = 1;
drvdata->pll[1].drvdata = drvdata;
drvdata->pll[1].hw.init = &init;
memset(&init, 0, sizeof(init));
if (drvdata->variant == SI5351_VARIANT_B) {
init.name = si5351_pll_names[2];
init.ops = &si5351_vxco_ops;
init.flags = 0;
init.parent_names = NULL;
init.num_parents = 0;
} else {
init.name = si5351_pll_names[1];
init.ops = &si5351_pll_ops;
init.flags = 0;
init.parent_names = parent_names;
init.num_parents = num_parents;
}
ret = devm_clk_hw_register(&client->dev, &drvdata->pll[1].hw);
if (ret) {
dev_err(&client->dev, "unable to register %s\n", init.name);
return ret;
}
/* register clk multisync and clk out divider */
num_clocks = (drvdata->variant == SI5351_VARIANT_A3) ? 3 : 8;
parent_names[0] = si5351_pll_names[0];
if (drvdata->variant == SI5351_VARIANT_B)
parent_names[1] = si5351_pll_names[2];
else
parent_names[1] = si5351_pll_names[1];
drvdata->msynth = devm_kcalloc(&client->dev, num_clocks,
sizeof(*drvdata->msynth), GFP_KERNEL);
drvdata->clkout = devm_kcalloc(&client->dev, num_clocks,
sizeof(*drvdata->clkout), GFP_KERNEL);
drvdata->num_clkout = num_clocks;
if (WARN_ON(!drvdata->msynth || !drvdata->clkout)) {
ret = -ENOMEM;
return ret;
}
for (n = 0; n < num_clocks; n++) {
drvdata->msynth[n].num = n;
drvdata->msynth[n].drvdata = drvdata;
drvdata->msynth[n].hw.init = &init;
memset(&init, 0, sizeof(init));
init.name = si5351_msynth_names[n];
init.ops = &si5351_msynth_ops;
init.flags = 0;
if (pdata->clkout[n].pll_master)
init.flags |= CLK_SET_RATE_PARENT;
init.parent_names = parent_names;
init.num_parents = 2;
ret = devm_clk_hw_register(&client->dev,
&drvdata->msynth[n].hw);
if (ret) {
dev_err(&client->dev, "unable to register %s\n",
init.name);
return ret;
}
}
num_parents = (drvdata->variant == SI5351_VARIANT_C) ? 4 : 3;
parent_names[2] = si5351_input_names[0];
parent_names[3] = si5351_input_names[1];
for (n = 0; n < num_clocks; n++) {
parent_names[0] = si5351_msynth_names[n];
parent_names[1] = (n < 4) ? si5351_msynth_names[0] :
si5351_msynth_names[4];
drvdata->clkout[n].num = n;
drvdata->clkout[n].drvdata = drvdata;
drvdata->clkout[n].hw.init = &init;
memset(&init, 0, sizeof(init));
init.name = si5351_clkout_names[n];
init.ops = &si5351_clkout_ops;
init.flags = 0;
if (pdata->clkout[n].clkout_src == SI5351_CLKOUT_SRC_MSYNTH_N)
init.flags |= CLK_SET_RATE_PARENT;
init.parent_names = parent_names;
init.num_parents = num_parents;
ret = devm_clk_hw_register(&client->dev,
&drvdata->clkout[n].hw);
if (ret) {
dev_err(&client->dev, "unable to register %s\n",
init.name);
return ret;
}
/* set initial clkout rate */
if (pdata->clkout[n].rate != 0) {
int ret;
ret = clk_set_rate(drvdata->clkout[n].hw.clk,
pdata->clkout[n].rate);
if (ret != 0) {
dev_err(&client->dev, "Cannot set rate : %d\n",
ret);
}
}
}
ret = devm_of_clk_add_hw_provider(&client->dev, si53351_of_clk_get,
drvdata);
if (ret) {
dev_err(&client->dev, "unable to add clk provider\n");
return ret;
}
return 0;
}
static struct i2c_driver si5351_driver = {
.driver = {
.name = "si5351",
.of_match_table = of_match_ptr(si5351_dt_ids),
},
.probe = si5351_i2c_probe,
.id_table = si5351_i2c_ids,
};
module_i2c_driver(si5351_driver);
MODULE_AUTHOR("Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com");
MODULE_DESCRIPTION("Silicon Labs Si5351A/B/C clock generator driver");
MODULE_LICENSE("GPL");
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