// SPDX-License-Identifier: GPL-2.0 /* * Driver for Silicon Labs Si5341/Si5340 Clock generator * Copyright (C) 2019 Topic Embedded Products * Author: Mike Looijmans */ #include #include #include #include #include #include #include #include #include #include #define SI5341_MAX_NUM_OUTPUTS 10 #define SI5340_MAX_NUM_OUTPUTS 4 #define SI5341_NUM_SYNTH 5 #define SI5340_NUM_SYNTH 4 /* Range of the synthesizer fractional divider */ #define SI5341_SYNTH_N_MIN 10 #define SI5341_SYNTH_N_MAX 4095 /* The chip can get its input clock from 3 input pins or an XTAL */ /* There is one PLL running at 13500–14256 MHz */ #define SI5341_PLL_VCO_MIN 13500000000ull #define SI5341_PLL_VCO_MAX 14256000000ull /* The 5 frequency synthesizers obtain their input from the PLL */ struct clk_si5341_synth { struct clk_hw hw; struct clk_si5341 *data; u8 index; }; #define to_clk_si5341_synth(_hw) \ container_of(_hw, struct clk_si5341_synth, hw) /* The output stages can be connected to any synth (full mux) */ struct clk_si5341_output { struct clk_hw hw; struct clk_si5341 *data; u8 index; }; #define to_clk_si5341_output(_hw) \ container_of(_hw, struct clk_si5341_output, hw) struct clk_si5341 { struct clk_hw hw; struct regmap *regmap; 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; const u16 *reg_output_offset; const u16 *reg_rdiv_offset; u64 freq_vco; /* 13500–14256 MHz */ u8 num_outputs; u8 num_synth; }; #define to_clk_si5341(_hw) container_of(_hw, struct clk_si5341, hw) struct clk_si5341_output_config { u8 out_format_drv_bits; u8 out_cm_ampl_bits; bool synth_master; bool always_on; }; #define SI5341_PAGE 0x0001 #define SI5341_PN_BASE 0x0002 #define SI5341_DEVICE_REV 0x0005 #define SI5341_STATUS 0x000C #define SI5341_SOFT_RST 0x001C /* Input dividers (48-bit) */ #define SI5341_IN_PDIV(x) (0x0208 + ((x) * 10)) #define SI5341_IN_PSET(x) (0x020E + ((x) * 10)) /* PLL configuration */ #define SI5341_PLL_M_NUM 0x0235 #define SI5341_PLL_M_DEN 0x023B /* Output configuration */ #define SI5341_OUT_CONFIG(output) \ ((output)->data->reg_output_offset[(output)->index]) #define SI5341_OUT_FORMAT(output) (SI5341_OUT_CONFIG(output) + 1) #define SI5341_OUT_CM(output) (SI5341_OUT_CONFIG(output) + 2) #define SI5341_OUT_MUX_SEL(output) (SI5341_OUT_CONFIG(output) + 3) #define SI5341_OUT_R_REG(output) \ ((output)->data->reg_rdiv_offset[(output)->index]) /* Synthesize N divider */ #define SI5341_SYNTH_N_NUM(x) (0x0302 + ((x) * 11)) #define SI5341_SYNTH_N_DEN(x) (0x0308 + ((x) * 11)) #define SI5341_SYNTH_N_UPD(x) (0x030C + ((x) * 11)) /* Synthesizer output enable, phase bypass, power mode */ #define SI5341_SYNTH_N_CLK_TO_OUTX_EN 0x0A03 #define SI5341_SYNTH_N_PIBYP 0x0A04 #define SI5341_SYNTH_N_PDNB 0x0A05 #define SI5341_SYNTH_N_CLK_DIS 0x0B4A #define SI5341_REGISTER_MAX 0xBFF /* SI5341_OUT_CONFIG bits */ #define SI5341_OUT_CFG_PDN BIT(0) #define SI5341_OUT_CFG_OE BIT(1) #define SI5341_OUT_CFG_RDIV_FORCE2 BIT(2) /* Static configuration (to be moved to firmware) */ struct si5341_reg_default { u16 address; u8 value; }; /* Output configuration registers 0..9 are not quite logically organized */ static const u16 si5341_reg_output_offset[] = { 0x0108, 0x010D, 0x0112, 0x0117, 0x011C, 0x0121, 0x0126, 0x012B, 0x0130, 0x013A, }; static const u16 si5340_reg_output_offset[] = { 0x0112, 0x0117, 0x0126, 0x012B, }; /* The location of the R divider registers */ static const u16 si5341_reg_rdiv_offset[] = { 0x024A, 0x024D, 0x0250, 0x0253, 0x0256, 0x0259, 0x025C, 0x025F, 0x0262, 0x0268, }; static const u16 si5340_reg_rdiv_offset[] = { 0x0250, 0x0253, 0x025C, 0x025F, }; /* * Programming sequence from ClockBuilder, settings to initialize the system * using only the XTAL input, without pre-divider. * This also contains settings that aren't mentioned anywhere in the datasheet. * The "known" settings like synth and output configuration are done later. */ static const struct si5341_reg_default si5341_reg_defaults[] = { { 0x0017, 0x3A }, /* INT mask (disable interrupts) */ { 0x0018, 0xFF }, /* INT mask */ { 0x0021, 0x0F }, /* Select XTAL as input */ { 0x0022, 0x00 }, /* Not in datasheet */ { 0x002B, 0x02 }, /* SPI config */ { 0x002C, 0x20 }, /* LOS enable for XTAL */ { 0x002D, 0x00 }, /* LOS timing */ { 0x002E, 0x00 }, { 0x002F, 0x00 }, { 0x0030, 0x00 }, { 0x0031, 0x00 }, { 0x0032, 0x00 }, { 0x0033, 0x00 }, { 0x0034, 0x00 }, { 0x0035, 0x00 }, { 0x0036, 0x00 }, { 0x0037, 0x00 }, { 0x0038, 0x00 }, /* LOS setting (thresholds) */ { 0x0039, 0x00 }, { 0x003A, 0x00 }, { 0x003B, 0x00 }, { 0x003C, 0x00 }, { 0x003D, 0x00 }, /* LOS setting (thresholds) end */ { 0x0041, 0x00 }, /* LOS0_DIV_SEL */ { 0x0042, 0x00 }, /* LOS1_DIV_SEL */ { 0x0043, 0x00 }, /* LOS2_DIV_SEL */ { 0x0044, 0x00 }, /* LOS3_DIV_SEL */ { 0x009E, 0x00 }, /* Not in datasheet */ { 0x0102, 0x01 }, /* Enable outputs */ { 0x013F, 0x00 }, /* Not in datasheet */ { 0x0140, 0x00 }, /* Not in datasheet */ { 0x0141, 0x40 }, /* OUT LOS */ { 0x0202, 0x00 }, /* XAXB_FREQ_OFFSET (=0)*/ { 0x0203, 0x00 }, { 0x0204, 0x00 }, { 0x0205, 0x00 }, { 0x0206, 0x00 }, /* PXAXB (2^x) */ { 0x0208, 0x00 }, /* Px divider setting (usually 0) */ { 0x0209, 0x00 }, { 0x020A, 0x00 }, { 0x020B, 0x00 }, { 0x020C, 0x00 }, { 0x020D, 0x00 }, { 0x020E, 0x00 }, { 0x020F, 0x00 }, { 0x0210, 0x00 }, { 0x0211, 0x00 }, { 0x0212, 0x00 }, { 0x0213, 0x00 }, { 0x0214, 0x00 }, { 0x0215, 0x00 }, { 0x0216, 0x00 }, { 0x0217, 0x00 }, { 0x0218, 0x00 }, { 0x0219, 0x00 }, { 0x021A, 0x00 }, { 0x021B, 0x00 }, { 0x021C, 0x00 }, { 0x021D, 0x00 }, { 0x021E, 0x00 }, { 0x021F, 0x00 }, { 0x0220, 0x00 }, { 0x0221, 0x00 }, { 0x0222, 0x00 }, { 0x0223, 0x00 }, { 0x0224, 0x00 }, { 0x0225, 0x00 }, { 0x0226, 0x00 }, { 0x0227, 0x00 }, { 0x0228, 0x00 }, { 0x0229, 0x00 }, { 0x022A, 0x00 }, { 0x022B, 0x00 }, { 0x022C, 0x00 }, { 0x022D, 0x00 }, { 0x022E, 0x00 }, { 0x022F, 0x00 }, /* Px divider setting (usually 0) end */ { 0x026B, 0x00 }, /* DESIGN_ID (ASCII string) */ { 0x026C, 0x00 }, { 0x026D, 0x00 }, { 0x026E, 0x00 }, { 0x026F, 0x00 }, { 0x0270, 0x00 }, { 0x0271, 0x00 }, { 0x0272, 0x00 }, /* DESIGN_ID (ASCII string) end */ { 0x0339, 0x1F }, /* N_FSTEP_MSK */ { 0x033B, 0x00 }, /* Nx_FSTEPW (Frequency step) */ { 0x033C, 0x00 }, { 0x033D, 0x00 }, { 0x033E, 0x00 }, { 0x033F, 0x00 }, { 0x0340, 0x00 }, { 0x0341, 0x00 }, { 0x0342, 0x00 }, { 0x0343, 0x00 }, { 0x0344, 0x00 }, { 0x0345, 0x00 }, { 0x0346, 0x00 }, { 0x0347, 0x00 }, { 0x0348, 0x00 }, { 0x0349, 0x00 }, { 0x034A, 0x00 }, { 0x034B, 0x00 }, { 0x034C, 0x00 }, { 0x034D, 0x00 }, { 0x034E, 0x00 }, { 0x034F, 0x00 }, { 0x0350, 0x00 }, { 0x0351, 0x00 }, { 0x0352, 0x00 }, { 0x0353, 0x00 }, { 0x0354, 0x00 }, { 0x0355, 0x00 }, { 0x0356, 0x00 }, { 0x0357, 0x00 }, { 0x0358, 0x00 }, /* Nx_FSTEPW (Frequency step) end */ { 0x0359, 0x00 }, /* Nx_DELAY */ { 0x035A, 0x00 }, { 0x035B, 0x00 }, { 0x035C, 0x00 }, { 0x035D, 0x00 }, { 0x035E, 0x00 }, { 0x035F, 0x00 }, { 0x0360, 0x00 }, { 0x0361, 0x00 }, { 0x0362, 0x00 }, /* Nx_DELAY end */ { 0x0802, 0x00 }, /* Not in datasheet */ { 0x0803, 0x00 }, /* Not in datasheet */ { 0x0804, 0x00 }, /* Not in datasheet */ { 0x090E, 0x02 }, /* XAXB_EXTCLK_EN=0 XAXB_PDNB=1 (use XTAL) */ { 0x091C, 0x04 }, /* ZDM_EN=4 (Normal mode) */ { 0x0943, 0x00 }, /* IO_VDD_SEL=0 (0=1v8, use 1=3v3) */ { 0x0949, 0x00 }, /* IN_EN (disable input clocks) */ { 0x094A, 0x00 }, /* INx_TO_PFD_EN (disabled) */ { 0x0A02, 0x00 }, /* Not in datasheet */ { 0x0B44, 0x0F }, /* PDIV_ENB (datasheet does not mention what it is) */ }; /* Read and interpret a 44-bit followed by a 32-bit value in the regmap */ static int si5341_decode_44_32(struct regmap *regmap, unsigned int reg, u64 *val1, u32 *val2) { int err; u8 r[10]; err = regmap_bulk_read(regmap, reg, r, 10); if (err < 0) return err; *val1 = ((u64)((r[5] & 0x0f) << 8 | r[4]) << 32) | (get_unaligned_le32(r)); *val2 = get_unaligned_le32(&r[6]); return 0; } static int si5341_encode_44_32(struct regmap *regmap, unsigned int reg, u64 n_num, u32 n_den) { u8 r[10]; /* Shift left as far as possible without overflowing */ while (!(n_num & BIT_ULL(43)) && !(n_den & BIT(31))) { n_num <<= 1; n_den <<= 1; } /* 44 bits (6 bytes) numerator */ put_unaligned_le32(n_num, r); r[4] = (n_num >> 32) & 0xff; r[5] = (n_num >> 40) & 0x0f; /* 32 bits denominator */ put_unaligned_le32(n_den, &r[6]); /* Program the fraction */ return regmap_bulk_write(regmap, reg, r, sizeof(r)); } /* VCO, we assume it runs at a constant frequency */ static unsigned long si5341_clk_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct clk_si5341 *data = to_clk_si5341(hw); int err; u64 res; u64 m_num; u32 m_den; unsigned int shift; /* Assume that PDIV is not being used, just read the PLL setting */ err = si5341_decode_44_32(data->regmap, SI5341_PLL_M_NUM, &m_num, &m_den); if (err < 0) return 0; if (!m_num || !m_den) return 0; /* * Though m_num is 64-bit, only the upper bits are actually used. While * calculating m_num and m_den, they are shifted as far as possible to * the left. To avoid 96-bit division here, we just shift them back so * we can do with just 64 bits. */ shift = 0; res = m_num; while (res & 0xffff00000000ULL) { ++shift; res >>= 1; } res *= parent_rate; do_div(res, (m_den >> shift)); /* We cannot return the actual frequency in 32 bit, store it locally */ data->freq_vco = res; /* Report kHz since the value is out of range */ do_div(res, 1000); return (unsigned long)res; } static const struct clk_ops si5341_clk_ops = { .recalc_rate = si5341_clk_recalc_rate, }; /* Synthesizers, there are 5 synthesizers that connect to any of the outputs */ /* The synthesizer is on if all power and enable bits are set */ static int si5341_synth_clk_is_on(struct clk_hw *hw) { struct clk_si5341_synth *synth = to_clk_si5341_synth(hw); int err; u32 val; u8 index = synth->index; err = regmap_read(synth->data->regmap, SI5341_SYNTH_N_CLK_TO_OUTX_EN, &val); if (err < 0) return 0; if (!(val & BIT(index))) return 0; err = regmap_read(synth->data->regmap, SI5341_SYNTH_N_PDNB, &val); if (err < 0) return 0; if (!(val & BIT(index))) return 0; /* This bit must be 0 for the synthesizer to receive clock input */ err = regmap_read(synth->data->regmap, SI5341_SYNTH_N_CLK_DIS, &val); if (err < 0) return 0; return !(val & BIT(index)); } static void si5341_synth_clk_unprepare(struct clk_hw *hw) { struct clk_si5341_synth *synth = to_clk_si5341_synth(hw); u8 index = synth->index; /* In range 0..5 */ u8 mask = BIT(index); /* Disable output */ regmap_update_bits(synth->data->regmap, SI5341_SYNTH_N_CLK_TO_OUTX_EN, mask, 0); /* Power down */ regmap_update_bits(synth->data->regmap, SI5341_SYNTH_N_PDNB, mask, 0); /* Disable clock input to synth (set to 1 to disable) */ regmap_update_bits(synth->data->regmap, SI5341_SYNTH_N_CLK_DIS, mask, mask); } static int si5341_synth_clk_prepare(struct clk_hw *hw) { struct clk_si5341_synth *synth = to_clk_si5341_synth(hw); int err; u8 index = synth->index; u8 mask = BIT(index); /* Power up */ err = regmap_update_bits(synth->data->regmap, SI5341_SYNTH_N_PDNB, mask, mask); if (err < 0) return err; /* Enable clock input to synth (set bit to 0 to enable) */ err = regmap_update_bits(synth->data->regmap, SI5341_SYNTH_N_CLK_DIS, mask, 0); if (err < 0) return err; /* Enable output */ return regmap_update_bits(synth->data->regmap, SI5341_SYNTH_N_CLK_TO_OUTX_EN, mask, mask); } /* Synth clock frequency: Fvco * n_den / n_den, with Fvco in 13500-14256 MHz */ static unsigned long si5341_synth_clk_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct clk_si5341_synth *synth = to_clk_si5341_synth(hw); u64 f; u64 n_num; u32 n_den; int err; err = si5341_decode_44_32(synth->data->regmap, SI5341_SYNTH_N_NUM(synth->index), &n_num, &n_den); if (err < 0) return err; /* * n_num and n_den are shifted left as much as possible, so to prevent * overflow in 64-bit math, we shift n_den 4 bits to the right */ f = synth->data->freq_vco; f *= n_den >> 4; /* Now we need to to 64-bit division: f/n_num */ /* And compensate for the 4 bits we dropped */ f = div64_u64(f, (n_num >> 4)); return f; } static long si5341_synth_clk_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *parent_rate) { struct clk_si5341_synth *synth = to_clk_si5341_synth(hw); u64 f; /* The synthesizer accuracy is such that anything in range will work */ f = synth->data->freq_vco; do_div(f, SI5341_SYNTH_N_MAX); if (rate < f) return f; f = synth->data->freq_vco; do_div(f, SI5341_SYNTH_N_MIN); if (rate > f) return f; return rate; } static int si5341_synth_program(struct clk_si5341_synth *synth, u64 n_num, u32 n_den, bool is_integer) { int err; u8 index = synth->index; err = si5341_encode_44_32(synth->data->regmap, SI5341_SYNTH_N_NUM(index), n_num, n_den); err = regmap_update_bits(synth->data->regmap, SI5341_SYNTH_N_PIBYP, BIT(index), is_integer ? BIT(index) : 0); if (err < 0) return err; return regmap_write(synth->data->regmap, SI5341_SYNTH_N_UPD(index), 0x01); } static int si5341_synth_clk_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { struct clk_si5341_synth *synth = to_clk_si5341_synth(hw); u64 n_num; u32 n_den; u32 r; u32 g; bool is_integer; n_num = synth->data->freq_vco; /* see if there's an integer solution */ r = do_div(n_num, rate); is_integer = (r == 0); if (is_integer) { /* Integer divider equal to n_num */ n_den = 1; } else { /* Calculate a fractional solution */ g = gcd(r, rate); n_den = rate / g; n_num *= n_den; n_num += r / g; } dev_dbg(&synth->data->i2c_client->dev, "%s(%u): n=0x%llx d=0x%x %s\n", __func__, synth->index, n_num, n_den, is_integer ? "int" : "frac"); return si5341_synth_program(synth, n_num, n_den, is_integer); } static const struct clk_ops si5341_synth_clk_ops = { .is_prepared = si5341_synth_clk_is_on, .prepare = si5341_synth_clk_prepare, .unprepare = si5341_synth_clk_unprepare, .recalc_rate = si5341_synth_clk_recalc_rate, .round_rate = si5341_synth_clk_round_rate, .set_rate = si5341_synth_clk_set_rate, }; static int si5341_output_clk_is_on(struct clk_hw *hw) { struct clk_si5341_output *output = to_clk_si5341_output(hw); int err; u32 val; err = regmap_read(output->data->regmap, SI5341_OUT_CONFIG(output), &val); if (err < 0) return err; /* Bit 0=PDN, 1=OE so only a value of 0x2 enables the output */ return (val & 0x03) == SI5341_OUT_CFG_OE; } /* Disables and then powers down the output */ static void si5341_output_clk_unprepare(struct clk_hw *hw) { struct clk_si5341_output *output = to_clk_si5341_output(hw); regmap_update_bits(output->data->regmap, SI5341_OUT_CONFIG(output), SI5341_OUT_CFG_OE, 0); regmap_update_bits(output->data->regmap, SI5341_OUT_CONFIG(output), SI5341_OUT_CFG_PDN, SI5341_OUT_CFG_PDN); } /* Powers up and then enables the output */ static int si5341_output_clk_prepare(struct clk_hw *hw) { struct clk_si5341_output *output = to_clk_si5341_output(hw); int err; err = regmap_update_bits(output->data->regmap, SI5341_OUT_CONFIG(output), SI5341_OUT_CFG_PDN, 0); if (err < 0) return err; return regmap_update_bits(output->data->regmap, SI5341_OUT_CONFIG(output), SI5341_OUT_CFG_OE, SI5341_OUT_CFG_OE); } static unsigned long si5341_output_clk_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct clk_si5341_output *output = to_clk_si5341_output(hw); int err; u32 val; u32 r_divider; u8 r[3]; err = regmap_bulk_read(output->data->regmap, SI5341_OUT_R_REG(output), r, 3); if (err < 0) return err; /* Calculate value as 24-bit integer*/ r_divider = r[2] << 16 | r[1] << 8 | r[0]; /* If Rx_REG is zero, the divider is disabled, so return a "0" rate */ if (!r_divider) return 0; /* Divider is 2*(Rx_REG+1) */ r_divider += 1; r_divider <<= 1; err = regmap_read(output->data->regmap, SI5341_OUT_CONFIG(output), &val); if (err < 0) return err; if (val & SI5341_OUT_CFG_RDIV_FORCE2) r_divider = 2; return parent_rate / r_divider; } static long si5341_output_clk_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *parent_rate) { unsigned long r; r = *parent_rate >> 1; /* If rate is an even divisor, no changes to parent required */ if (r && !(r % rate)) return (long)rate; if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) { if (rate > 200000000) { /* minimum r-divider is 2 */ r = 2; } else { /* Take a parent frequency near 400 MHz */ r = (400000000u / rate) & ~1; } *parent_rate = r * rate; } else { /* We cannot change our parent's rate, report what we can do */ r /= rate; rate = *parent_rate / (r << 1); } return rate; } static int si5341_output_clk_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { struct clk_si5341_output *output = to_clk_si5341_output(hw); /* Frequency divider is (r_div + 1) * 2 */ u32 r_div = (parent_rate / rate) >> 1; int err; u8 r[3]; if (r_div <= 1) r_div = 0; else if (r_div >= BIT(24)) r_div = BIT(24) - 1; else --r_div; /* For a value of "2", we set the "OUT0_RDIV_FORCE2" bit */ err = regmap_update_bits(output->data->regmap, SI5341_OUT_CONFIG(output), SI5341_OUT_CFG_RDIV_FORCE2, (r_div == 0) ? SI5341_OUT_CFG_RDIV_FORCE2 : 0); if (err < 0) return err; /* Always write Rx_REG, because a zero value disables the divider */ r[0] = r_div ? (r_div & 0xff) : 1; r[1] = (r_div >> 8) & 0xff; r[2] = (r_div >> 16) & 0xff; err = regmap_bulk_write(output->data->regmap, SI5341_OUT_R_REG(output), r, 3); return 0; } static int si5341_output_reparent(struct clk_si5341_output *output, u8 index) { return regmap_update_bits(output->data->regmap, SI5341_OUT_MUX_SEL(output), 0x07, index); } static int si5341_output_set_parent(struct clk_hw *hw, u8 index) { struct clk_si5341_output *output = to_clk_si5341_output(hw); if (index >= output->data->num_synth) return -EINVAL; return si5341_output_reparent(output, index); } static u8 si5341_output_get_parent(struct clk_hw *hw) { struct clk_si5341_output *output = to_clk_si5341_output(hw); int err; u32 val; err = regmap_read(output->data->regmap, SI5341_OUT_MUX_SEL(output), &val); return val & 0x7; } static const struct clk_ops si5341_output_clk_ops = { .is_prepared = si5341_output_clk_is_on, .prepare = si5341_output_clk_prepare, .unprepare = si5341_output_clk_unprepare, .recalc_rate = si5341_output_clk_recalc_rate, .round_rate = si5341_output_clk_round_rate, .set_rate = si5341_output_clk_set_rate, .set_parent = si5341_output_set_parent, .get_parent = si5341_output_get_parent, }; /* * The chip can be bought in a pre-programmed version, or one can program the * NVM in the chip to boot up in a preset mode. This routine tries to determine * if that's the case, or if we need to reset and program everything from * scratch. Returns negative error, or true/false. */ static int si5341_is_programmed_already(struct clk_si5341 *data) { int err; u8 r[4]; /* Read the PLL divider value, it must have a non-zero value */ err = regmap_bulk_read(data->regmap, SI5341_PLL_M_DEN, r, ARRAY_SIZE(r)); if (err < 0) return err; return !!get_unaligned_le32(r); } static struct clk_hw * of_clk_si5341_get(struct of_phandle_args *clkspec, void *_data) { struct clk_si5341 *data = _data; unsigned int idx = clkspec->args[1]; unsigned int group = clkspec->args[0]; switch (group) { case 0: if (idx >= data->num_outputs) { dev_err(&data->i2c_client->dev, "invalid output index %u\n", idx); return ERR_PTR(-EINVAL); } return &data->clk[idx].hw; case 1: if (idx >= data->num_synth) { dev_err(&data->i2c_client->dev, "invalid synthesizer index %u\n", idx); return ERR_PTR(-EINVAL); } return &data->synth[idx].hw; case 2: if (idx > 0) { dev_err(&data->i2c_client->dev, "invalid PLL index %u\n", idx); return ERR_PTR(-EINVAL); } return &data->hw; default: dev_err(&data->i2c_client->dev, "invalid group %u\n", group); return ERR_PTR(-EINVAL); } } static int si5341_probe_chip_id(struct clk_si5341 *data) { int err; u8 reg[4]; u16 model; err = regmap_bulk_read(data->regmap, SI5341_PN_BASE, reg, ARRAY_SIZE(reg)); if (err < 0) { dev_err(&data->i2c_client->dev, "Failed to read chip ID\n"); return err; } model = get_unaligned_le16(reg); dev_info(&data->i2c_client->dev, "Chip: %x Grade: %u Rev: %u\n", model, reg[2], reg[3]); switch (model) { case 0x5340: data->num_outputs = SI5340_MAX_NUM_OUTPUTS; data->num_synth = SI5340_NUM_SYNTH; data->reg_output_offset = si5340_reg_output_offset; data->reg_rdiv_offset = si5340_reg_rdiv_offset; break; case 0x5341: data->num_outputs = SI5341_MAX_NUM_OUTPUTS; data->num_synth = SI5341_NUM_SYNTH; data->reg_output_offset = si5341_reg_output_offset; data->reg_rdiv_offset = si5341_reg_rdiv_offset; break; default: dev_err(&data->i2c_client->dev, "Model '%x' not supported\n", model); return -EINVAL; } return 0; } /* Read active settings into the regmap cache for later reference */ static int si5341_read_settings(struct clk_si5341 *data) { int err; u8 i; u8 r[10]; err = regmap_bulk_read(data->regmap, SI5341_PLL_M_NUM, r, 10); if (err < 0) return err; err = regmap_bulk_read(data->regmap, SI5341_SYNTH_N_CLK_TO_OUTX_EN, r, 3); if (err < 0) return err; err = regmap_bulk_read(data->regmap, SI5341_SYNTH_N_CLK_DIS, r, 1); if (err < 0) return err; for (i = 0; i < data->num_synth; ++i) { err = regmap_bulk_read(data->regmap, SI5341_SYNTH_N_NUM(i), r, 10); if (err < 0) return err; } for (i = 0; i < data->num_outputs; ++i) { err = regmap_bulk_read(data->regmap, data->reg_output_offset[i], r, 4); if (err < 0) return err; err = regmap_bulk_read(data->regmap, data->reg_rdiv_offset[i], r, 3); if (err < 0) return err; } return 0; } static int si5341_write_multiple(struct clk_si5341 *data, const struct si5341_reg_default *values, unsigned int num_values) { unsigned int i; int res; for (i = 0; i < num_values; ++i) { res = regmap_write(data->regmap, values[i].address, values[i].value); if (res < 0) { dev_err(&data->i2c_client->dev, "Failed to write %#x:%#x\n", values[i].address, values[i].value); return res; } } return 0; } static const struct si5341_reg_default si5341_preamble[] = { { 0x0B25, 0x00 }, { 0x0502, 0x01 }, { 0x0505, 0x03 }, { 0x0957, 0x1F }, { 0x0B4E, 0x1A }, }; static int si5341_send_preamble(struct clk_si5341 *data) { int res; u32 revision; /* For revision 2 and up, the values are slightly different */ res = regmap_read(data->regmap, SI5341_DEVICE_REV, &revision); if (res < 0) return res; /* Write "preamble" as specified by datasheet */ res = regmap_write(data->regmap, 0xB24, revision < 2 ? 0xD8 : 0xC0); if (res < 0) return res; res = si5341_write_multiple(data, si5341_preamble, ARRAY_SIZE(si5341_preamble)); if (res < 0) return res; /* Datasheet specifies a 300ms wait after sending the preamble */ msleep(300); return 0; } /* Perform a soft reset and write post-amble */ static int si5341_finalize_defaults(struct clk_si5341 *data) { int res; u32 revision; res = regmap_read(data->regmap, SI5341_DEVICE_REV, &revision); if (res < 0) return res; dev_dbg(&data->i2c_client->dev, "%s rev=%u\n", __func__, revision); res = regmap_write(data->regmap, SI5341_SOFT_RST, 0x01); if (res < 0) return res; /* Datasheet does not explain these nameless registers */ res = regmap_write(data->regmap, 0xB24, revision < 2 ? 0xDB : 0xC3); if (res < 0) return res; res = regmap_write(data->regmap, 0x0B25, 0x02); if (res < 0) return res; return 0; } 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 */ 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)), regmap_reg_range(SI5341_SYNTH_N_UPD(3), SI5341_SYNTH_N_UPD(3)), regmap_reg_range(SI5341_SYNTH_N_UPD(4), SI5341_SYNTH_N_UPD(4)), }; static const struct regmap_access_table si5341_regmap_volatile = { .yes_ranges = si5341_regmap_volatile_range, .n_yes_ranges = ARRAY_SIZE(si5341_regmap_volatile_range), }; /* Pages 0, 1, 2, 3, 9, A, B are valid, so there are 12 pages */ static const struct regmap_range_cfg si5341_regmap_ranges[] = { { .range_min = 0, .range_max = SI5341_REGISTER_MAX, .selector_reg = SI5341_PAGE, .selector_mask = 0xff, .selector_shift = 0, .window_start = 0, .window_len = 256, }, }; static const struct regmap_config si5341_regmap_config = { .reg_bits = 8, .val_bits = 8, .cache_type = REGCACHE_RBTREE, .ranges = si5341_regmap_ranges, .num_ranges = ARRAY_SIZE(si5341_regmap_ranges), .max_register = SI5341_REGISTER_MAX, .volatile_table = &si5341_regmap_volatile, }; static int si5341_dt_parse_dt(struct i2c_client *client, struct clk_si5341_output_config *config) { struct device_node *child; struct device_node *np = client->dev.of_node; u32 num; u32 val; memset(config, 0, sizeof(struct clk_si5341_output_config) * SI5341_MAX_NUM_OUTPUTS); for_each_child_of_node(np, child) { if (of_property_read_u32(child, "reg", &num)) { dev_err(&client->dev, "missing reg property of %s\n", child->name); goto put_child; } if (num >= SI5341_MAX_NUM_OUTPUTS) { dev_err(&client->dev, "invalid clkout %d\n", num); goto put_child; } if (!of_property_read_u32(child, "silabs,format", &val)) { /* Set cm and ampl conservatively to 3v3 settings */ switch (val) { case 1: /* normal differential */ config[num].out_cm_ampl_bits = 0x33; break; case 2: /* low-power differential */ config[num].out_cm_ampl_bits = 0x13; break; case 4: /* LVCMOS */ config[num].out_cm_ampl_bits = 0x33; /* Set SI recommended impedance for LVCMOS */ config[num].out_format_drv_bits |= 0xc0; break; default: dev_err(&client->dev, "invalid silabs,format %u for %u\n", val, num); goto put_child; } config[num].out_format_drv_bits &= ~0x07; config[num].out_format_drv_bits |= val & 0x07; /* Always enable the SYNC feature */ config[num].out_format_drv_bits |= 0x08; } if (!of_property_read_u32(child, "silabs,common-mode", &val)) { if (val > 0xf) { dev_err(&client->dev, "invalid silabs,common-mode %u\n", val); goto put_child; } config[num].out_cm_ampl_bits &= 0xf0; config[num].out_cm_ampl_bits |= val & 0x0f; } if (!of_property_read_u32(child, "silabs,amplitude", &val)) { if (val > 0xf) { dev_err(&client->dev, "invalid silabs,amplitude %u\n", val); goto put_child; } config[num].out_cm_ampl_bits &= 0x0f; config[num].out_cm_ampl_bits |= (val << 4) & 0xf0; } if (of_property_read_bool(child, "silabs,disable-high")) config[num].out_format_drv_bits |= 0x10; config[num].synth_master = of_property_read_bool(child, "silabs,synth-master"); config[num].always_on = of_property_read_bool(child, "always-on"); } return 0; put_child: of_node_put(child); return -EINVAL; } /* * If not pre-configured, calculate and set the PLL configuration manually. * For low-jitter performance, the PLL should be set such that the synthesizers * only need integer division. * Without any user guidance, we'll set the PLL to 14GHz, which still allows * the chip to generate any frequency on its outputs, but jitter performance * may be sub-optimal. */ 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; if (of_property_read_u32(np, "silabs,pll-m-num", &m_num)) { dev_err(&data->i2c_client->dev, "PLL configuration requires silabs,pll-m-num\n"); } if (of_property_read_u32(np, "silabs,pll-m-den", &m_den)) { dev_err(&data->i2c_client->dev, "PLL configuration requires silabs,pll-m-den\n"); } 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; m_num = 1400000000; } return si5341_encode_44_32(data->regmap, SI5341_PLL_M_NUM, m_num, m_den); } static int si5341_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct clk_si5341 *data; struct clk_init_data init; const char *root_clock_name; const char *synth_clock_names[SI5341_NUM_SYNTH]; int err; unsigned int i; struct clk_si5341_output_config config[SI5341_MAX_NUM_OUTPUTS]; bool initialization_required; data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM; 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"); } err = si5341_dt_parse_dt(client, config); if (err) return err; if (of_property_read_string(client->dev.of_node, "clock-output-names", &init.name)) init.name = client->dev.of_node->name; root_clock_name = init.name; data->regmap = devm_regmap_init_i2c(client, &si5341_regmap_config); if (IS_ERR(data->regmap)) return PTR_ERR(data->regmap); i2c_set_clientdata(client, data); err = si5341_probe_chip_id(data); 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 { err = si5341_is_programmed_already(data); if (err < 0) return err; initialization_required = !err; } if (initialization_required) { /* Populate the regmap cache in preparation for "cache only" */ err = si5341_read_settings(data); if (err < 0) return err; err = si5341_send_preamble(data); if (err < 0) return err; /* * We intend to send all 'final' register values in a single * transaction. So cache all register writes until we're done * configuring. */ regcache_cache_only(data->regmap, true); /* Write the configuration pairs from the firmware blob */ err = si5341_write_multiple(data, si5341_reg_defaults, ARRAY_SIZE(si5341_reg_defaults)); if (err < 0) return err; /* PLL configuration is required */ err = si5341_initialize_pll(data); if (err < 0) return err; } /* 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.ops = &si5341_clk_ops; init.flags = 0; data->hw.init = &init; err = devm_clk_hw_register(&client->dev, &data->hw); if (err) { dev_err(&client->dev, "clock registration failed\n"); return err; } init.num_parents = 1; init.parent_names = &root_clock_name; init.ops = &si5341_synth_clk_ops; for (i = 0; i < data->num_synth; ++i) { synth_clock_names[i] = devm_kasprintf(&client->dev, GFP_KERNEL, "%s.N%u", client->dev.of_node->name, i); init.name = synth_clock_names[i]; data->synth[i].index = i; data->synth[i].data = data; data->synth[i].hw.init = &init; err = devm_clk_hw_register(&client->dev, &data->synth[i].hw); if (err) { dev_err(&client->dev, "synth N%u registration failed\n", i); } } init.num_parents = data->num_synth; init.parent_names = synth_clock_names; init.ops = &si5341_output_clk_ops; for (i = 0; i < data->num_outputs; ++i) { init.name = kasprintf(GFP_KERNEL, "%s.%d", client->dev.of_node->name, i); init.flags = config[i].synth_master ? CLK_SET_RATE_PARENT : 0; data->clk[i].index = i; data->clk[i].data = data; data->clk[i].hw.init = &init; if (config[i].out_format_drv_bits & 0x07) { regmap_write(data->regmap, SI5341_OUT_FORMAT(&data->clk[i]), config[i].out_format_drv_bits); regmap_write(data->regmap, SI5341_OUT_CM(&data->clk[i]), config[i].out_cm_ampl_bits); } err = devm_clk_hw_register(&client->dev, &data->clk[i].hw); kfree(init.name); /* clock framework made a copy of the name */ if (err) { dev_err(&client->dev, "output %u registration failed\n", i); return err; } if (config[i].always_on) clk_prepare(data->clk[i].hw.clk); } err = of_clk_add_hw_provider(client->dev.of_node, of_clk_si5341_get, data); if (err) { dev_err(&client->dev, "unable to add clk provider\n"); return err; } if (initialization_required) { /* Synchronize */ regcache_cache_only(data->regmap, false); err = regcache_sync(data->regmap); if (err < 0) return err; err = si5341_finalize_defaults(data); if (err < 0) return err; } /* Free the names, clk framework makes copies */ for (i = 0; i < data->num_synth; ++i) devm_kfree(&client->dev, (void *)synth_clock_names[i]); return 0; } static const struct i2c_device_id si5341_id[] = { { "si5340", 0 }, { "si5341", 1 }, { } }; MODULE_DEVICE_TABLE(i2c, si5341_id); static const struct of_device_id clk_si5341_of_match[] = { { .compatible = "silabs,si5340" }, { .compatible = "silabs,si5341" }, { } }; MODULE_DEVICE_TABLE(of, clk_si5341_of_match); static struct i2c_driver si5341_driver = { .driver = { .name = "si5341", .of_match_table = clk_si5341_of_match, }, .probe = si5341_probe, .id_table = si5341_id, }; module_i2c_driver(si5341_driver); MODULE_AUTHOR("Mike Looijmans "); MODULE_DESCRIPTION("Si5341 driver"); MODULE_LICENSE("GPL");