Re: [PATCH 08/13] clk: add AD24xx clock driver

From: Alvin Šipraga
Date: Fri May 17 2024 - 09:19:06 EST

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Previous message: Rob Herring (Arm): "Re: [PATCH] arm64: dts: mt7622: fix switch probe on bananapi-r64"
In reply to: Alvin Šipraga: "[PATCH 08/13] clk: add AD24xx clock driver"
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Please ignore this patch. b4 broke down half way through sending the
series due to an error from my mail server. I have fixed things up and
the full series can be viewed here:

https://lore.kernel.org/all/20240517-a2b-v1-0-b8647554c67b@xxxxxxxxxxxxxxx/#t
Message-Id: <20240517-a2b-v1-0-b8647554c67b@xxxxxxxxxxxxxxx>

Thank you.

On Fri, May 17, 2024 at 03:02:15PM GMT, Alvin Šipraga wrote:
> From: Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>
>
> Analog Devices Inc. AD24xx series A2B transceivers support muxing IO
> pins to a CLKOUT function. The clock supports division of the internal
> PLL of the transceiver.
>
> Signed-off-by: Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>
> ---
> drivers/a2b/Kconfig | 1 +
> drivers/clk/Kconfig | 7 +
> drivers/clk/Makefile | 1 +
> drivers/clk/clk-ad24xx.c | 341 +++++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 350 insertions(+)
>
> diff --git a/drivers/a2b/Kconfig b/drivers/a2b/Kconfig
> index 6ba5dc11c51d..08acf5728023 100644
> --- a/drivers/a2b/Kconfig
> +++ b/drivers/a2b/Kconfig
> @@ -35,6 +35,7 @@ config A2B_AD24XX_NODE
> select REGMAP_A2B
> imply GPIO_AD24XX
> imply SND_SOC_AD24XX
> + imply COMMON_CLK_AD24XX
> help
> Say Y here to enable support for AD24xx A2B transceiver nodes. This
> applies to both main nodes and subordinate nodes. Supported models
> diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
> index 3e9099504fad..a3d54b077e68 100644
> --- a/drivers/clk/Kconfig
> +++ b/drivers/clk/Kconfig
> @@ -257,6 +257,13 @@ config COMMON_CLK_LAN966X
> LAN966X SoC. GCK generates and supplies clock to various peripherals
> within the SoC.
>
> +config COMMON_CLK_AD24XX
> + bool "Clock driver for Analog Devices Inc. AD24xx"
> + depends on A2B_AD24XX_NODE
> + help
> + This driver supports the clock output functionality of AD24xx series
> + A2B transceiver chips.
> +
> config COMMON_CLK_ASPEED
> bool "Clock driver for Aspeed BMC SoCs"
> depends on ARCH_ASPEED || COMPILE_TEST
> diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
> index 4abe16c8ccdf..cf5c867bf71a 100644
> --- a/drivers/clk/Makefile
> +++ b/drivers/clk/Makefile
> @@ -36,6 +36,7 @@ obj-$(CONFIG_COMMON_CLK_FIXED_MMIO) += clk-fixed-mmio.o
> obj-$(CONFIG_COMMON_CLK_FSL_FLEXSPI) += clk-fsl-flexspi.o
> obj-$(CONFIG_COMMON_CLK_FSL_SAI) += clk-fsl-sai.o
> obj-$(CONFIG_COMMON_CLK_GEMINI) += clk-gemini.o
> +obj-$(CONFIG_COMMON_CLK_AD24XX) += clk-ad24xx.o
> obj-$(CONFIG_COMMON_CLK_ASPEED) += clk-aspeed.o
> obj-$(CONFIG_MACH_ASPEED_G6) += clk-ast2600.o
> obj-$(CONFIG_ARCH_HIGHBANK) += clk-highbank.o
> diff --git a/drivers/clk/clk-ad24xx.c b/drivers/clk/clk-ad24xx.c
> new file mode 100644
> index 000000000000..ed227c317faa
> --- /dev/null
> +++ b/drivers/clk/clk-ad24xx.c
> @@ -0,0 +1,341 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * AD24xx clock driver
> + *
> + * Copyright (c) 2023 Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>
> + */
> +
> +#include <linux/a2b/a2b.h>
> +#include <linux/a2b/ad24xx.h>
> +#include <linux/clk-provider.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +
> +#define AD24XX_NUM_CLKS 2
> +
> +/* Define some safe macros to make the code more readable */
> +#define A2B_CLKCFG(_idx) (!(_idx) ? A2B_CLK1CFG : A2B_CLK2CFG)
> +
> +#define A2B_CLKCFG_DIV_SHIFT A2B_CLK1CFG_CLK1DIV_SHIFT
> +#define A2B_CLKCFG_PDIV_SHIFT A2B_CLK1CFG_CLK1PDIV_SHIFT
> +
> +#define A2B_CLKCFG_DIV_MASK A2B_CLK1CFG_CLK1DIV_MASK
> +#define A2B_CLKCFG_PDIV_MASK A2B_CLK1CFG_CLK1PDIV_MASK
> +#define A2B_CLKCFG_INV_MASK A2B_CLK1CFG_CLK1INV_MASK
> +#define A2B_CLKCFG_EN_MASK A2B_CLK1CFG_CLK1EN_MASK
> +
> +static_assert(A2B_CLK1CFG_CLK1DIV_MASK == A2B_CLK2CFG_CLK2DIV_MASK);
> +static_assert(A2B_CLK1CFG_CLK1PDIV_MASK == A2B_CLK2CFG_CLK2PDIV_MASK);
> +static_assert(A2B_CLK1CFG_CLK1INV_MASK == A2B_CLK2CFG_CLK2INV_MASK);
> +static_assert(A2B_CLK1CFG_CLK1EN_MASK == A2B_CLK2CFG_CLK2EN_MASK);
> +
> +struct ad24xx_clkout {
> + struct clk_hw hw;
> + unsigned int idx;
> + bool registered;
> +};
> +
> +struct ad24xx_clk {
> + struct device *dev;
> + struct a2b_func *func;
> + struct a2b_node *node;
> + struct regmap *regmap;
> + struct clk_hw *pll_hw;
> + struct ad24xx_clkout clkouts[AD24XX_NUM_CLKS];
> +};
> +
> +static struct ad24xx_clkout *to_ad24xx_clkout(struct clk_hw *hw)
> +{
> + return container_of(hw, struct ad24xx_clkout, hw);
> +}
> +
> +static struct ad24xx_clk *to_ad24xx_clk(struct ad24xx_clkout *clkout)
> +{
> + return container_of(clkout, struct ad24xx_clk, clkouts[clkout->idx]);
> +}
> +
> +/*
> + * A CLKOUT signal is derived from the PLL frequency (2048 * SFF), going through
> + * a pre-divide step and a divide step.
> + *
> + * The pre-divide is either 2 or 32. The divisor is between 1 and 16.
> + *
> + * The pre-divide register PDIV is 1 bit and selects between 2 (0) or 32 (1).
> + * The divide register DIV is 4 bit and the resultant divisor is 2 * (DIV + 1).
> + */
> +
> +#define VAL(_pdiv, _div) \
> + (((_pdiv) << A2B_CLKCFG_PDIV_SHIFT) | ((_div) << A2B_CLKCFG_DIV_SHIFT))
> +#define DIV(_div) (2 * ((_div) + 1))
> +
> +/* In total there are 6 bits to the value, with the 4th bit going unused */
> +#define AD24XX_CLK_DIV_WIDTH 6
> +static const struct clk_div_table ad24xx_clk_div_table[] = {
> + { VAL(0, 0), 2 * DIV(0) }, { VAL(0, 1), 2 * DIV(1) },
> + { VAL(0, 2), 2 * DIV(2) }, { VAL(0, 3), 2 * DIV(3) },
> + { VAL(0, 4), 2 * DIV(4) }, { VAL(0, 5), 2 * DIV(5) },
> + { VAL(0, 6), 2 * DIV(6) }, { VAL(0, 7), 2 * DIV(7) },
> + { VAL(0, 8), 2 * DIV(8) }, { VAL(0, 9), 2 * DIV(9) },
> + { VAL(0, 10), 2 * DIV(10) }, { VAL(0, 11), 2 * DIV(11) },
> + { VAL(0, 12), 2 * DIV(12) }, { VAL(0, 13), 2 * DIV(13) },
> + { VAL(0, 14), 2 * DIV(14) }, { VAL(0, 15), 2 * DIV(15) },
> + { VAL(1, 0), 32 * DIV(0) }, { VAL(1, 1), 32 * DIV(1) },
> + { VAL(1, 2), 32 * DIV(2) }, { VAL(1, 3), 32 * DIV(3) },
> + { VAL(1, 4), 32 * DIV(4) }, { VAL(1, 5), 32 * DIV(5) },
> + { VAL(1, 6), 32 * DIV(6) }, { VAL(1, 7), 32 * DIV(7) },
> + { VAL(1, 8), 32 * DIV(8) }, { VAL(1, 9), 32 * DIV(9) },
> + { VAL(1, 10), 32 * DIV(10) }, { VAL(1, 11), 32 * DIV(11) },
> + { VAL(1, 12), 32 * DIV(12) }, { VAL(1, 13), 32 * DIV(13) },
> + { VAL(1, 14), 32 * DIV(14) }, { VAL(1, 15), 32 * DIV(15) },
> + { /* sentinel */ }
> +};
> +
> +static int ad24xx_clk_prepare(struct clk_hw *hw)
> +{
> + struct ad24xx_clkout *clkout = to_ad24xx_clkout(hw);
> + struct ad24xx_clk *adclk = to_ad24xx_clk(clkout);
> + unsigned int idx = clkout->idx;
> +
> + return regmap_update_bits(adclk->regmap, A2B_CLKCFG(idx),
> + A2B_CLKCFG_EN_MASK,
> + FIELD_PREP(A2B_CLKCFG_EN_MASK, 1));
> +}
> +
> +static void ad24xx_clk_unprepare(struct clk_hw *hw)
> +{
> + struct ad24xx_clkout *clkout = to_ad24xx_clkout(hw);
> + struct ad24xx_clk *adclk = to_ad24xx_clk(clkout);
> + unsigned int idx = clkout->idx;
> +
> + regmap_update_bits(adclk->regmap, A2B_CLKCFG(idx), A2B_CLKCFG_EN_MASK,
> + FIELD_PREP(A2B_CLKCFG_EN_MASK, 0));
> +}
> +
> +static unsigned long ad24xx_clk_recalc_rate(struct clk_hw *hw,
> + unsigned long parent_rate)
> +{
> + struct ad24xx_clkout *clkout = to_ad24xx_clkout(hw);
> + struct ad24xx_clk *adclk = to_ad24xx_clk(clkout);
> + unsigned int idx = clkout->idx;
> + unsigned int val;
> + int ret;
> +
> + ret = regmap_read(adclk->regmap, A2B_CLKCFG(idx), &val);
> + if (ret)
> + return 0;
> +
> + val &= A2B_CLKCFG_PDIV_MASK | A2B_CLKCFG_DIV_MASK;
> +
> + return divider_recalc_rate(hw, parent_rate, val, ad24xx_clk_div_table,
> + 0, AD24XX_CLK_DIV_WIDTH);
> +}
> +
> +static long ad24xx_clk_round_rate(struct clk_hw *hw, unsigned long rate,
> + unsigned long *parent_rate)
> +{
> + return divider_round_rate(hw, rate, parent_rate, ad24xx_clk_div_table,
> + AD24XX_CLK_DIV_WIDTH, 0);
> +}
> +
> +static int ad24xx_clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
> +{
> + return divider_determine_rate(hw, req, ad24xx_clk_div_table,
> + AD24XX_CLK_DIV_WIDTH, 0);
> +}
> +
> +static int ad24xx_clk_set_rate(struct clk_hw *hw, unsigned long rate,
> + unsigned long parent_rate)
> +{
> + struct ad24xx_clkout *clkout = to_ad24xx_clkout(hw);
> + struct ad24xx_clk *adclk = to_ad24xx_clk(clkout);
> + unsigned int idx = clkout->idx;
> + int val;
> +
> + val = divider_get_val(rate, parent_rate, ad24xx_clk_div_table,
> + AD24XX_CLK_DIV_WIDTH, 0);
> + if (val < 0)
> + return val;
> +
> + return regmap_update_bits(adclk->regmap, A2B_CLKCFG(idx),
> + A2B_CLKCFG_PDIV_MASK | A2B_CLKCFG_DIV_MASK,
> + val);
> +}
> +
> +static int ad24xx_clk_get_phase(struct clk_hw *hw)
> +{
> + struct ad24xx_clkout *clkout = to_ad24xx_clkout(hw);
> + struct ad24xx_clk *adclk = to_ad24xx_clk(clkout);
> + unsigned int idx = clkout->idx;
> + unsigned int val;
> + bool invert;
> + int ret;
> +
> + ret = regmap_read(adclk->regmap, A2B_CLKCFG(idx), &val);
> + if (ret)
> + return ret;
> +
> + invert = FIELD_GET(A2B_CLKCFG_INV_MASK, val);
> +
> + return invert ? 180 : 0;
> +}
> +
> +static int ad24xx_clk_set_phase(struct clk_hw *hw, int degrees)
> +{
> + struct ad24xx_clkout *clkout = to_ad24xx_clkout(hw);
> + struct ad24xx_clk *adclk = to_ad24xx_clk(clkout);
> + unsigned int idx = clkout->idx;
> + bool invert = !!degrees;
> +
> + if (degrees != 0 && degrees != 180)
> + return -EINVAL;
> +
> + return regmap_update_bits(adclk->regmap, A2B_CLKCFG(idx),
> + A2B_CLKCFG_INV_MASK,
> + FIELD_PREP(A2B_CLKCFG_INV_MASK, invert));
> +}
> +
> +static const struct clk_ops ad24xx_clk_ops = {
> + .prepare = ad24xx_clk_prepare,
> + .unprepare = ad24xx_clk_unprepare,
> + .recalc_rate = ad24xx_clk_recalc_rate,
> + .round_rate = ad24xx_clk_round_rate,
> + .determine_rate = ad24xx_clk_determine_rate,
> + .set_rate = ad24xx_clk_set_rate,
> + .get_phase = ad24xx_clk_get_phase,
> + .set_phase = ad24xx_clk_set_phase,
> +};
> +
> +static const struct regmap_config ad24xx_clk_regmap_config = {
> + .reg_bits = 8,
> + .val_bits = 8,
> + .cache_type = REGCACHE_RBTREE,
> +};
> +
> +static struct clk_hw *ad24xx_clk_of_get(struct of_phandle_args *clkspec, void *data)
> +{
> + struct ad24xx_clk *adclk = data;
> + unsigned int idx = clkspec->args[0];
> +
> + if (idx >= AD24XX_NUM_CLKS)
> + return ERR_PTR(-EINVAL);
> +
> + if (!adclk->clkouts[idx].registered)
> + return ERR_PTR(-ENOENT);
> +
> + return &adclk->clkouts[idx].hw;
> +}
> +
> +static int ad24xx_clk_probe(struct device *dev)
> +{
> + struct a2b_func *func = to_a2b_func(dev);
> + struct a2b_node *node = func->node;
> + struct device_node *np = dev->of_node;
> + char *pll_name;
> + const char *sync_clk_name;
> + struct ad24xx_clk *adclk;
> + int num_clks;
> + int ret;
> + int i;
> +
> + /*
> + * Older series AD240x and AD241x chips have a single discrete
> + * A2B_CLKCFG register that behaves differently to the A2B_CLKnCFG
> + * registers of the later AD242x series. This driver only supports the
> + * latter right now.
> + */
> + if (!(node->chip_info->caps & A2B_CHIP_CAP_CLKOUT))
> + return -ENODEV;
> +
> + adclk = devm_kzalloc(dev, sizeof(*adclk), GFP_KERNEL);
> + if (!adclk)
> + return -ENOMEM;
> +
> + adclk->regmap =
> + devm_regmap_init_a2b_func(func, &ad24xx_clk_regmap_config);
> + if (IS_ERR(adclk->regmap))
> + return PTR_ERR(adclk->regmap);
> +
> + adclk->dev = dev;
> + adclk->func = func;
> + adclk->node = node;
> + dev_set_drvdata(dev, adclk);
> +
> + num_clks = of_property_count_strings(np, "clock-output-names");
> + if (num_clks < 0 || num_clks > AD24XX_NUM_CLKS)
> + return -EINVAL;
> +
> + /*
> + * Register the PLL internally to use it as the parent of the CLKOUTs.
> + * The PLL runs at 2048 times the SYNC clock rate.
> + */
> + pll_name =
> + devm_kasprintf(dev, GFP_KERNEL, "%s_pll", dev_name(&node->dev));
> + if (!pll_name)
> + return -ENOMEM;
> + sync_clk_name = __clk_get_name(a2b_node_get_sync_clk(func->node));
> + adclk->pll_hw = devm_clk_hw_register_fixed_factor(
> + dev, pll_name, sync_clk_name, 0, 2048, 1);
> + if (IS_ERR(adclk->pll_hw))
> + return PTR_ERR(adclk->pll_hw);
> +
> + for (i = 0; i < num_clks; i++) {
> + struct clk_init_data init = { };
> + const char *parent_names = clk_hw_get_name(adclk->pll_hw);
> + unsigned int idx = i;
> +
> + /* Clock outputs can be skipped with the clock-indices property */
> + of_property_read_u32_index(np, "clock-indices", i, &idx);
> + if (idx > AD24XX_NUM_CLKS)
> + return -EINVAL;
> +
> + ret = of_property_read_string_index(np, "clock-output-names", i,
> + &init.name);
> + if (ret)
> + return ret;
> +
> + init.ops = &ad24xx_clk_ops;
> + init.parent_names = &parent_names;
> + init.num_parents = 1;
> +
> + adclk->clkouts[idx].hw.init = &init;
> + adclk->clkouts[idx].idx = idx;
> + adclk->clkouts[idx].registered = true;
> +
> + ret = devm_clk_hw_register(dev, &adclk->clkouts[idx].hw);
> + if (ret)
> + return ret;
> + }
> +
> + ret = devm_of_clk_add_hw_provider(dev, ad24xx_clk_of_get, adclk);
> + if (ret)
> + return ret;
> +
> + return 0;
> +}
> +
> +static const struct of_device_id ad24xx_clk_of_match_table[] = {
> + { .compatible = "adi,ad2420-clk" },
> + { .compatible = "adi,ad2421-clk" },
> + { .compatible = "adi,ad2422-clk" },
> + { .compatible = "adi,ad2425-clk" },
> + { .compatible = "adi,ad2426-clk" },
> + { .compatible = "adi,ad2427-clk" },
> + { .compatible = "adi,ad2428-clk" },
> + { .compatible = "adi,ad2429-clk" },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, ad24xx_clk_of_match_table);
> +
> +static struct a2b_driver ad24xx_clk_driver = {
> + .driver = {
> + .name = "ad24xx-clk",
> + .of_match_table = ad24xx_clk_of_match_table,
> + .probe_type = PROBE_PREFER_ASYNCHRONOUS,
> + },
> + .probe = ad24xx_clk_probe,
> +};
> +module_a2b_driver(ad24xx_clk_driver);
> +
> +MODULE_AUTHOR("Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("AD24xx CLK driver");
> +MODULE_LICENSE("GPL");
>
> --
> 2.44.0
>

Next message: Mikhail Gavrilov: "6.10/regression/bisected - commit a68c7eaa7a8f cause *ERROR* Trying to clear memory with ring turned off in amdgpu_fill_buffer."
Previous message: Rob Herring (Arm): "Re: [PATCH] arm64: dts: mt7622: fix switch probe on bananapi-r64"
In reply to: Alvin Šipraga: "[PATCH 08/13] clk: add AD24xx clock driver"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]