Clkdiv module provides a clock output on the PMIC with CXO as the source. This clock can be routed through PMIC GPIOs. Add a device driver to configure this clkdiv module. Signed-off-by: Tirupathi Reddy <tirupath@xxxxxxxxxxxxxx> --- .../bindings/clock/clk-spmi-pmic-div.txt | 51 +++ drivers/clk/qcom/Kconfig | 9 + drivers/clk/qcom/Makefile | 1 + drivers/clk/qcom/clk-spmi-pmic-div.c | 342 +++++++++++++++++++++ 4 files changed, 403 insertions(+) create mode 100644 Documentation/devicetree/bindings/clock/clk-spmi-pmic-div.txt create mode 100644 drivers/clk/qcom/clk-spmi-pmic-div.c diff --git a/Documentation/devicetree/bindings/clock/clk-spmi-pmic-div.txt b/Documentation/devicetree/bindings/clock/clk-spmi-pmic-div.txt new file mode 100644 index 0000000..8b84b32 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/clk-spmi-pmic-div.txt @@ -0,0 +1,51 @@ +Qualcomm Technologies, Inc. SPMI PMIC clock divider (clkdiv) + +clkdiv configures the clock frequency of a set of outputs on the PMIC. +These clocks are typically wired through alternate functions on +gpio pins. + +======================= +Properties +======================= + +- compatible + Usage: required + Value type: <string> + Definition: must be one of: + "qcom,spmi-clkdiv" + "qcom,pm8998-clkdiv" + +- reg + Usage: required + Value type: <prop-encoded-array> + Definition: Addresses and sizes for the memory of this CLKDIV + peripheral. + +- clocks: + Usage: required + Value type: <prop-encoded-array> + Definition: reference to the xo clock. + +- clock-names: + Usage: required + Value type: <stringlist> + Definition: must be "xo". + +======= +Example +======= + +pm8998_clk_divs: qcom,clkdiv@5b00 { + compatible = "qcom,pm8998-clkdiv"; + reg = <0x5b00>; + #clock-cells = <1>; + clocks = <&xo_board>; + clock-names = "xo"; + + assigned-clocks = <&pm8998_clk_divs 1>, + <&pm8998_clk_divs 2>, + <&pm8998_clk_divs 3>; + assigned-clock-rates = <9600000>, + <9600000>, + <9600000>; +}; diff --git a/drivers/clk/qcom/Kconfig b/drivers/clk/qcom/Kconfig index 9f6c278..dd5b18e 100644 --- a/drivers/clk/qcom/Kconfig +++ b/drivers/clk/qcom/Kconfig @@ -196,3 +196,12 @@ config MSM_MMCC_8996 Support for the multimedia clock controller on msm8996 devices. Say Y if you want to support multimedia devices such as display, graphics, video encode/decode, camera, etc. + +config SPMI_PMIC_CLKDIV + tristate "spmi pmic clkdiv driver" + depends on (COMMON_CLK_QCOM && SPMI) || COMPILE_TEST + help + This driver supports the clkdiv functionality on the Qualcomm + Technologies, Inc. SPMI PMIC. It configures the frequency of + clkdiv outputs on the PMIC. These clocks are typically wired + through alternate functions on gpio pins. diff --git a/drivers/clk/qcom/Makefile b/drivers/clk/qcom/Makefile index 3f3aff2..4d4c62b 100644 --- a/drivers/clk/qcom/Makefile +++ b/drivers/clk/qcom/Makefile @@ -33,3 +33,4 @@ obj-$(CONFIG_MSM_MMCC_8974) += mmcc-msm8974.o obj-$(CONFIG_MSM_MMCC_8996) += mmcc-msm8996.o obj-$(CONFIG_QCOM_CLK_RPM) += clk-rpm.o obj-$(CONFIG_QCOM_CLK_SMD_RPM) += clk-smd-rpm.o +obj-$(CONFIG_SPMI_PMIC_CLKDIV) += clk-spmi-pmic-div.o diff --git a/drivers/clk/qcom/clk-spmi-pmic-div.c b/drivers/clk/qcom/clk-spmi-pmic-div.c new file mode 100644 index 0000000..2a71b64 --- /dev/null +++ b/drivers/clk/qcom/clk-spmi-pmic-div.c @@ -0,0 +1,342 @@ +/* Copyright (c) 2017, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/log2.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> +#include <linux/types.h> + +#define REG_DIV_CTL1 0x43 +#define DIV_CTL1_DIV_FACTOR_MASK GENMASK(2, 0) + +#define REG_EN_CTL 0x46 +#define REG_EN_MASK BIT(7) + +#define ENABLE_DELAY_NS(cxo_ns, div) ((2 + 3 * div) * cxo_ns) +#define DISABLE_DELAY_NS(cxo_ns, div) ((3 * div) * cxo_ns) + +#define CLK_SPMI_PMIC_DIV_OFFSET 1 + +#define CLKDIV_XO_DIV_1_0 0 +#define CLKDIV_XO_DIV_1 1 +#define CLKDIV_XO_DIV_2 2 +#define CLKDIV_XO_DIV_4 3 +#define CLKDIV_XO_DIV_8 4 +#define CLKDIV_XO_DIV_16 5 +#define CLKDIV_XO_DIV_32 6 +#define CLKDIV_XO_DIV_64 7 +#define CLKDIV_MAX_ALLOWED 8 + +struct clkdiv { + struct regmap *regmap; + u16 base; + spinlock_t lock; + + /* clock properties */ + struct clk_hw hw; + unsigned int div_factor; + unsigned int cxo_period_ns; +}; + +static inline struct clkdiv *to_clkdiv(struct clk_hw *hw) +{ + return container_of(hw, struct clkdiv, hw); +} + +static inline unsigned int div_factor_to_div(unsigned int div_factor) +{ + if (div_factor == CLKDIV_XO_DIV_1_0) + return 1; + + return 1 << (div_factor - CLK_SPMI_PMIC_DIV_OFFSET); +} + +static inline unsigned int div_to_div_factor(unsigned int div) +{ + return min(ilog2(div) + CLK_SPMI_PMIC_DIV_OFFSET, + CLKDIV_MAX_ALLOWED - 1); +} + +static bool is_spmi_pmic_clkdiv_enabled(struct clkdiv *clkdiv) +{ + unsigned int val = 0; + + regmap_read(clkdiv->regmap, clkdiv->base + REG_EN_CTL, + &val); + return (val & REG_EN_MASK) ? true : false; +} + +static int spmi_pmic_clkdiv_set_enable_state(struct clkdiv *clkdiv, + bool enable_state) +{ + int rc; + + rc = regmap_update_bits(clkdiv->regmap, clkdiv->base + REG_EN_CTL, + REG_EN_MASK, + (enable_state == true) ? REG_EN_MASK : 0); + if (rc) + return rc; + + if (enable_state == true) + ndelay(ENABLE_DELAY_NS(clkdiv->cxo_period_ns, + div_factor_to_div(clkdiv->div_factor))); + else + ndelay(DISABLE_DELAY_NS(clkdiv->cxo_period_ns, + div_factor_to_div(clkdiv->div_factor))); + + return rc; +} + +static int spmi_pmic_clkdiv_config_freq_div(struct clkdiv *clkdiv, + unsigned int div) +{ + unsigned int div_factor; + unsigned long flags; + bool enabled; + int rc; + + div_factor = div_to_div_factor(div); + + spin_lock_irqsave(&clkdiv->lock, flags); + + enabled = is_spmi_pmic_clkdiv_enabled(clkdiv); + if (enabled) { + rc = spmi_pmic_clkdiv_set_enable_state(clkdiv, false); + if (rc) + goto fail; + } + + rc = regmap_update_bits(clkdiv->regmap, + clkdiv->base + REG_DIV_CTL1, + DIV_CTL1_DIV_FACTOR_MASK, div_factor); + if (rc) + goto fail; + + clkdiv->div_factor = div_factor; + + if (enabled) + rc = spmi_pmic_clkdiv_set_enable_state(clkdiv, true); + +fail: + spin_unlock_irqrestore(&clkdiv->lock, flags); + return rc; +} + +static int clk_spmi_pmic_div_enable(struct clk_hw *hw) +{ + struct clkdiv *clkdiv = to_clkdiv(hw); + unsigned long flags; + int rc; + + spin_lock_irqsave(&clkdiv->lock, flags); + rc = spmi_pmic_clkdiv_set_enable_state(clkdiv, true); + spin_unlock_irqrestore(&clkdiv->lock, flags); + + return rc; +} + +static void clk_spmi_pmic_div_disable(struct clk_hw *hw) +{ + struct clkdiv *clkdiv = to_clkdiv(hw); + unsigned long flags; + + spin_lock_irqsave(&clkdiv->lock, flags); + spmi_pmic_clkdiv_set_enable_state(clkdiv, false); + spin_unlock_irqrestore(&clkdiv->lock, flags); +} + +static long clk_spmi_pmic_div_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + unsigned long new_rate; + unsigned int div, div_factor; + + div = DIV_ROUND_UP(*parent_rate, rate); + div_factor = div_to_div_factor(div); + new_rate = *parent_rate / div_factor_to_div(div_factor); + + return new_rate; +} + +static unsigned long clk_spmi_pmic_div_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clkdiv *clkdiv = to_clkdiv(hw); + unsigned long rate; + + rate = parent_rate / div_factor_to_div(clkdiv->div_factor); + + return rate; +} + +static int clk_spmi_pmic_div_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clkdiv *clkdiv = to_clkdiv(hw); + + return spmi_pmic_clkdiv_config_freq_div(clkdiv, parent_rate / rate); +} + +static const struct clk_ops clk_spmi_pmic_div_ops = { + .enable = clk_spmi_pmic_div_enable, + .disable = clk_spmi_pmic_div_disable, + .set_rate = clk_spmi_pmic_div_set_rate, + .recalc_rate = clk_spmi_pmic_div_recalc_rate, + .round_rate = clk_spmi_pmic_div_round_rate, +}; + +struct spmi_pmic_div_clk_cc { + struct clk_hw **div_clks; + int nclks; +}; + +#define SPMI_PMIC_CLKDIV_MIN_INDEX 1 + +static struct clk_hw *spmi_pmic_div_clk_hw_get(struct of_phandle_args *clkspec, + void *data) +{ + struct spmi_pmic_div_clk_cc *clk_cc = data; + unsigned int idx = (clkspec->args[0] - SPMI_PMIC_CLKDIV_MIN_INDEX); + + if (idx < 0 || idx >= clk_cc->nclks) { + pr_err("%s: index value %u is invalid; allowed range: [%d, %d]\n", + __func__, SPMI_PMIC_CLKDIV_MIN_INDEX, clk_cc->nclks); + return ERR_PTR(-EINVAL); + } + + return clk_cc->div_clks[idx]; +} + +#define SPMI_PMIC_DIV_CLK_SIZE 0x100 + +static const struct of_device_id spmi_pmic_clkdiv_match_table[] = { + { + .compatible = "qcom,spmi-clkdiv", + .data = (void *)(uintptr_t)1, /* Generic */ + }, + { + .compatible = "qcom,pm8998-clkdiv", + .data = (void *)(uintptr_t)3, /* 3 div_clks */ + }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, spmi_pmic_clkdiv_match_table); + +static int spmi_pmic_clkdiv_probe(struct platform_device *pdev) +{ + struct spmi_pmic_div_clk_cc *clk_cc; + struct clk_init_data init = {}; + struct clkdiv *clkdiv; + struct clk *cxo; + struct regmap *regmap; + struct device *dev = &pdev->dev; + const char *parent_name; + int nclks, i, rc, cxo_hz; + u32 start; + + rc = of_property_read_u32(dev->of_node, "reg", &start); + if (rc < 0) { + dev_err(dev, "reg property reading failed\n"); + return rc; + } + + regmap = dev_get_regmap(dev->parent, NULL); + if (!regmap) { + dev_err(dev, "Couldn't get parent's regmap\n"); + return -EINVAL; + } + + nclks = (uintptr_t)of_match_node(spmi_pmic_clkdiv_match_table, + dev->of_node)->data; + + clkdiv = devm_kcalloc(dev, nclks, sizeof(*clkdiv), GFP_KERNEL); + if (!clkdiv) + return -ENOMEM; + + clk_cc = devm_kzalloc(&pdev->dev, sizeof(*clk_cc), GFP_KERNEL); + if (!clk_cc) + return -ENOMEM; + + clk_cc->div_clks = devm_kcalloc(&pdev->dev, nclks, + sizeof(*clk_cc->div_clks), GFP_KERNEL); + if (!clk_cc->div_clks) + return -ENOMEM; + + cxo = clk_get(dev, "xo"); + if (IS_ERR(cxo)) { + rc = PTR_ERR(cxo); + if (rc != -EPROBE_DEFER) + dev_err(dev, "failed to get xo clock"); + return rc; + } + cxo_hz = clk_get_rate(cxo); + clk_put(cxo); + + parent_name = of_clk_get_parent_name(dev->of_node, 0); + if (!parent_name) { + dev_err(dev, "missing parent clock\n"); + return -ENODEV; + } + + init.parent_names = &parent_name; + init.num_parents = parent_name ? 1 : 0; + init.ops = &clk_spmi_pmic_div_ops; + init.flags = 0; + + for (i = 0; i < nclks; i++) { + spin_lock_init(&clkdiv[i].lock); + clkdiv[i].base = start + i * SPMI_PMIC_DIV_CLK_SIZE; + clkdiv[i].regmap = regmap; + clkdiv[i].cxo_period_ns = NSEC_PER_SEC / cxo_hz; + init.name = kasprintf(GFP_KERNEL, "div_clk%d", i + 1); + clkdiv[i].hw.init = &init; + rc = devm_clk_hw_register(dev, &clkdiv[i].hw); + kfree(init.name); /* clock framework made a copy of the name */ + if (rc) + return rc; + + clk_cc->div_clks[i] = &clkdiv[i].hw; + } + + clk_cc->nclks = nclks; + rc = of_clk_add_hw_provider(pdev->dev.of_node, spmi_pmic_div_clk_hw_get, + clk_cc); + return rc; +} + +static int spmi_pmic_clkdiv_remove(struct platform_device *pdev) +{ + of_clk_del_provider(pdev->dev.of_node); + + return 0; +} + +static struct platform_driver spmi_pmic_clkdiv_driver = { + .driver = { + .name = "qcom,spmi-pmic-clkdiv", + .of_match_table = spmi_pmic_clkdiv_match_table, + }, + .probe = spmi_pmic_clkdiv_probe, + .remove = spmi_pmic_clkdiv_remove, +}; +module_platform_driver(spmi_pmic_clkdiv_driver); + +MODULE_DESCRIPTION("QCOM SPMI PMIC clkdiv driver"); +MODULE_LICENSE("GPL v2"); -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html