Palmas devices has two clock output CLK32K_KG and CLK32K_KG_AUDIO which can be enable/disable through software. Add clock driver support for the Palmas 32KHz clocks. Signed-off-by: Laxman Dewangan <ldewangan@xxxxxxxxxx> --- Changes from V1: - Call prepare if the clk is needed for boot-enable or sleep control. - change is_enabled to is_prepared. - Added ops palmas_clks_recalc_rate. - Added of_clk_add_provider(). Changes from V2: - Convert magic number to defines. Changes from V3: - Drop the option of clock enable at boot. - Add the dt-binding header for DTS file and added macros for ext pin and clock id. - Rephrase some of sentences. - Error check on init conifgurations. - Code cleanups for getting rid of some of enums. .../devicetree/bindings/clock/clk-palmas.txt | 50 +++ drivers/clk/Kconfig | 7 + drivers/clk/Makefile | 1 + drivers/clk/clk-palmas.c | 333 ++++++++++++++++++++ include/dt-bindings/mfd/palmas.h | 22 ++ 5 files changed, 413 insertions(+), 0 deletions(-) create mode 100644 Documentation/devicetree/bindings/clock/clk-palmas.txt create mode 100644 drivers/clk/clk-palmas.c create mode 100644 include/dt-bindings/mfd/palmas.h diff --git a/Documentation/devicetree/bindings/clock/clk-palmas.txt b/Documentation/devicetree/bindings/clock/clk-palmas.txt new file mode 100644 index 0000000..907c454 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/clk-palmas.txt @@ -0,0 +1,50 @@ +* Palmas 32KHz clocks * + +Palmas device has two clock output pins for 32KHz, KG and KG_AUDIO. + +This binding uses the common clock binding ./clock-bindings.txt. + +Required properties: +- compatible : shall be "ti,palmas-clk". +- #clock-cells : from common clock binding; shall be set to 1. The clock id for + different clocks are: + 0 for CLK32K_KG + 1 for CLK32K_KG_AUDIO. + The macros of clocks id for DTS is defined at + dt-bindings/mfd/palmas.h + +Optional subnode: + The clock node has optional subnode to provide the init configuration of + clocks like sleep control. + + The subnode name is fixed and it should be + clk32k_kg for the 32KHz KG clock. + clk32k_kg_audio for the 32KHz KG_AUDIO clock. + + Optional subnode properties: + ti,external-sleep-control: The external enable input pins controlled the + enable/disable of clocks. The external enable input pins ENABLE1, + ENABLE2 and NSLEEP. The valid values for the external pins are: + 1 for ENABLE1 + 2 for ENABLE2 + 3 for NSLEEP. + Option 0 or missing this property means the clock is + enabled/disabled via register access and these pins do + not have any control. + The macros of external control pins for DTS is defined at + dt-bindings/mfd/palmas.h + +Example: + #include <dt-bindings/mfd/palmas.h> + ... + palmas: tps65913@58 { + ... + clock { + compatible = "ti,palmas-clk"; + #clock-cells = <1>; + clk32k_kg { + ti,external-sleep-control = <PALMAS_EXT_CONTROL_PIN_NSLEEP>; + }; + }; + ... + }; diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index 279407a..6b8c233 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -93,6 +93,13 @@ config CLK_PPC_CORENET This adds the clock driver support for Freescale PowerPC corenet platforms using common clock framework. +config COMMON_CLK_PALMAS + tristate "Clock driver for TI Palmas devices" + depends on MFD_PALMAS + ---help--- + This driver supports TI Palmas devices 32KHz output KG and KG_AUDIO + using common clock framework. + endmenu source "drivers/clk/mvebu/Kconfig" diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index 7b11106..32e04cf 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -43,3 +43,4 @@ obj-$(CONFIG_COMMON_CLK_SI5351) += clk-si5351.o obj-$(CONFIG_COMMON_CLK_S2MPS11) += clk-s2mps11.o obj-$(CONFIG_CLK_TWL6040) += clk-twl6040.o obj-$(CONFIG_CLK_PPC_CORENET) += clk-ppc-corenet.o +obj-$(CONFIG_COMMON_CLK_PALMAS) += clk-palmas.o diff --git a/drivers/clk/clk-palmas.c b/drivers/clk/clk-palmas.c new file mode 100644 index 0000000..e6e56d1 --- /dev/null +++ b/drivers/clk/clk-palmas.c @@ -0,0 +1,333 @@ +/* + * Clock driver for Palmas device. + * + * Copyright (c) 2013, NVIDIA Corporation. + * + * Author: Laxman Dewangan <ldewangan@xxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind, + * whether express or implied; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + * 02111-1307, USA + */ + +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/mfd/palmas.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#define PALMAS_CLOCK_MAX 2 + +#define PALMAS_CLOCK_DT_EXT_CONTROL_ENABLE1 1 +#define PALMAS_CLOCK_DT_EXT_CONTROL_ENABLE2 2 +#define PALMAS_CLOCK_DT_EXT_CONTROL_NSLEEP 3 + +struct palmas_clks; + +struct palmas_clk32k_desc { + const char *clk_name; + unsigned int control_reg; + unsigned int enable_mask; + unsigned int sleep_mask; + unsigned int sleep_reqstr_id; +}; + +struct palmas_clock_info { + struct clk *clk; + struct clk_hw hw; + struct palmas_clk32k_desc *clk_desc; + struct palmas_clks *palmas_clk; + int ext_control_pin; +}; + +struct palmas_clks { + struct device *dev; + struct palmas *palmas; + struct clk_onecell_data clk_data; + struct palmas_clock_info clk_info[PALMAS_CLOCK_MAX]; +}; + +static struct palmas_clk32k_desc palmas_clk32k_descs[] = { + { + .clk_name = "clk32k_kg", + .control_reg = PALMAS_CLK32KG_CTRL, + .enable_mask = PALMAS_CLK32KG_CTRL_MODE_ACTIVE, + .sleep_mask = PALMAS_CLK32KG_CTRL_MODE_SLEEP, + .sleep_reqstr_id = PALMAS_EXTERNAL_REQSTR_ID_CLK32KG, + }, { + .clk_name = "clk32k_kg_audio", + .control_reg = PALMAS_CLK32KGAUDIO_CTRL, + .enable_mask = PALMAS_CLK32KG_CTRL_MODE_ACTIVE, + .sleep_mask = PALMAS_CLK32KG_CTRL_MODE_SLEEP, + .sleep_reqstr_id = PALMAS_EXTERNAL_REQSTR_ID_CLK32KGAUDIO, + }, +}; + +static inline struct palmas_clock_info *to_palmas_clks_info(struct clk_hw *hw) +{ + return container_of(hw, struct palmas_clock_info, hw); +} + +static unsigned long palmas_clks_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + return 32768; +} + +static int palmas_clks_prepare(struct clk_hw *hw) +{ + struct palmas_clock_info *cinfo = to_palmas_clks_info(hw); + struct palmas_clks *palmas_clks = cinfo->palmas_clk; + int ret; + + ret = palmas_update_bits(palmas_clks->palmas, PALMAS_RESOURCE_BASE, + cinfo->clk_desc->control_reg, + cinfo->clk_desc->enable_mask, + cinfo->clk_desc->enable_mask); + if (ret < 0) + dev_err(palmas_clks->dev, "Reg 0x%02x update failed, %d\n", + cinfo->clk_desc->control_reg, ret); + + return ret; +} + +static void palmas_clks_unprepare(struct clk_hw *hw) +{ + struct palmas_clock_info *cinfo = to_palmas_clks_info(hw); + struct palmas_clks *palmas_clks = cinfo->palmas_clk; + int ret; + + /* + * Clock can be disabled through external pin if it is externally + * controlled. + */ + if (cinfo->ext_control_pin) + return; + + ret = palmas_update_bits(palmas_clks->palmas, PALMAS_RESOURCE_BASE, + cinfo->clk_desc->control_reg, + cinfo->clk_desc->enable_mask, 0); + if (ret < 0) + dev_err(palmas_clks->dev, "Reg 0x%02x update failed, %d\n", + cinfo->clk_desc->control_reg, ret); + +} + +static int palmas_clks_is_prepared(struct clk_hw *hw) +{ + struct palmas_clock_info *cinfo = to_palmas_clks_info(hw); + struct palmas_clks *palmas_clks = cinfo->palmas_clk; + int ret; + u32 val; + + if (cinfo->ext_control_pin) + return 1; + + ret = palmas_read(palmas_clks->palmas, PALMAS_RESOURCE_BASE, + cinfo->clk_desc->control_reg, &val); + if (ret < 0) { + dev_err(palmas_clks->dev, "Reg 0x%02x read failed, %d\n", + cinfo->clk_desc->control_reg, ret); + return ret; + } + return !!(val & cinfo->clk_desc->enable_mask); +} + +static struct clk_ops palmas_clks_ops = { + .prepare = palmas_clks_prepare, + .unprepare = palmas_clks_unprepare, + .is_prepared = palmas_clks_is_prepared, + .recalc_rate = palmas_clks_recalc_rate, +}; + +static struct clk_init_data palmas_clks_hw_init[PALMAS_CLOCK_MAX] = { + { + .name = "clk32k_kg", + .ops = &palmas_clks_ops, + .flags = CLK_IS_ROOT | CLK_IGNORE_UNUSED, + }, { + .name = "clk32k_kg_audio", + .ops = &palmas_clks_ops, + .flags = CLK_IS_ROOT | CLK_IGNORE_UNUSED, + }, +}; + +static int palmas_clks_get_clk_data(struct platform_device *pdev, + struct palmas_clks *palmas_clks) +{ + struct device_node *node = pdev->dev.of_node; + struct device_node *child; + struct palmas_clock_info *cinfo; + unsigned int prop; + int ret; + int i; + + for (i = 0; i < PALMAS_CLOCK_MAX; ++i) { + child = of_get_child_by_name(node, + palmas_clk32k_descs[i].clk_name); + if (!child) + continue; + + cinfo = &palmas_clks->clk_info[i]; + + ret = of_property_read_u32(child, "ti,external-sleep-control", + &prop); + if (!ret) { + switch (prop) { + case PALMAS_CLOCK_DT_EXT_CONTROL_ENABLE1: + prop = PALMAS_EXT_CONTROL_ENABLE1; + break; + case PALMAS_CLOCK_DT_EXT_CONTROL_ENABLE2: + prop = PALMAS_EXT_CONTROL_ENABLE2; + break; + case PALMAS_CLOCK_DT_EXT_CONTROL_NSLEEP: + prop = PALMAS_EXT_CONTROL_NSLEEP; + break; + default: + WARN_ON(1); + dev_warn(&pdev->dev, + "%s: Invalid ext control option: %u\n", + child->name, prop); + prop = 0; + break; + } + cinfo->ext_control_pin = prop; + } + } + + return 0; +} + +static int palmas_clks_init_configure(struct palmas_clock_info *cinfo) +{ + struct palmas_clks *palmas_clks = cinfo->palmas_clk; + int ret; + + ret = palmas_update_bits(palmas_clks->palmas, PALMAS_RESOURCE_BASE, + cinfo->clk_desc->control_reg, + cinfo->clk_desc->sleep_mask, 0); + if (ret < 0) { + dev_err(palmas_clks->dev, "Reg 0x%02x update failed, %d\n", + cinfo->clk_desc->control_reg, ret); + return ret; + } + + if (cinfo->ext_control_pin) { + ret = clk_prepare(cinfo->clk); + if (ret < 0) { + dev_err(palmas_clks->dev, + "Clock prep failed, %d\n", ret); + return ret; + } + + ret = palmas_ext_control_req_config(palmas_clks->palmas, + cinfo->clk_desc->sleep_reqstr_id, + cinfo->ext_control_pin, true); + if (ret < 0) { + dev_err(palmas_clks->dev, + "Ext config for %s failed, %d\n", + cinfo->clk_desc->clk_name, ret); + return ret; + } + } + + return ret; +} + +static int palmas_clks_probe(struct platform_device *pdev) +{ + struct palmas *palmas = dev_get_drvdata(pdev->dev.parent); + struct palmas_clock_info *cinfo; + struct palmas_clks *palmas_clks; + struct clk *clk; + int i, ret; + + palmas_clks = devm_kzalloc(&pdev->dev, sizeof(*palmas_clks), + GFP_KERNEL); + if (!palmas_clks) + return -ENOMEM; + + palmas_clks->clk_data.clks = devm_kzalloc(&pdev->dev, + PALMAS_CLOCK_MAX * sizeof(*palmas_clks->clk_data.clks), + GFP_KERNEL); + if (!palmas_clks->clk_data.clks) + return -ENOMEM; + + palmas_clks_get_clk_data(pdev, palmas_clks); + platform_set_drvdata(pdev, palmas_clks); + + palmas_clks->dev = &pdev->dev; + palmas_clks->palmas = palmas; + + for (i = 0; i < PALMAS_CLOCK_MAX; i++) { + cinfo = &palmas_clks->clk_info[i]; + cinfo->clk_desc = &palmas_clk32k_descs[i]; + cinfo->hw.init = &palmas_clks_hw_init[i]; + cinfo->palmas_clk = palmas_clks; + clk = devm_clk_register(&pdev->dev, &cinfo->hw); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + dev_err(&pdev->dev, "Fail to register clock %s, %d\n", + palmas_clk32k_descs[i].clk_name, ret); + return ret; + } + + cinfo->clk = clk; + palmas_clks->clk_data.clks[i] = clk; + palmas_clks->clk_data.clk_num++; + ret = palmas_clks_init_configure(cinfo); + if (ret < 0) { + dev_err(&pdev->dev, "Clock config failed, %d\n", ret); + return ret; + } + } + + ret = of_clk_add_provider(pdev->dev.of_node, of_clk_src_simple_get, + &palmas_clks->clk_data); + if (ret < 0) + dev_err(&pdev->dev, "Fail to add clock driver, %d\n", ret); + return ret; +} + +static int palmas_clks_remove(struct platform_device *pdev) +{ + of_clk_del_provider(pdev->dev.of_node); + return 0; +} + +static struct of_device_id of_palmas_clks_match_tbl[] = { + { .compatible = "ti,palmas-clk", }, + {}, +}; +MODULE_DEVICE_TABLE(of, of_palmas_clks_match_tbl); + +static struct platform_driver palmas_clks_driver = { + .driver = { + .name = "palmas-clk", + .owner = THIS_MODULE, + .of_match_table = of_palmas_clks_match_tbl, + }, + .probe = palmas_clks_probe, + .remove = palmas_clks_remove, +}; + +module_platform_driver(palmas_clks_driver); + +MODULE_DESCRIPTION("Clock driver for Palmas Series Devices"); +MODULE_ALIAS("platform:palmas-clk"); +MODULE_AUTHOR("Laxman Dewangan <ldewangan@xxxxxxxxxx>"); +MODULE_LICENSE("GPL v2"); diff --git a/include/dt-bindings/mfd/palmas.h b/include/dt-bindings/mfd/palmas.h new file mode 100644 index 0000000..dcfa5fc --- /dev/null +++ b/include/dt-bindings/mfd/palmas.h @@ -0,0 +1,22 @@ +/* + * This header provides macros for Palmas device bindings. + * + * Copyright (c) 2013, NVIDIA Corporation. + * + * Author: Laxman Dewangan <ldewangan@xxxxxxxxxx> + * + */ + +#ifndef __DT_BINDINGS_PALMAS_H__ +#define __DT_BINDINGS_PALMAS_H + +/* External control pins */ +#define PALMAS_EXT_CONTROL_PIN_ENABLE1 1 +#define PALMAS_EXT_CONTROL_PIN_ENABLE2 2 +#define PALMAS_EXT_CONTROL_PIN_NSLEEP 3 + +/* Palmas device's clocks id */ +#define PALMAS_CLOCKS_CLK32K_KG 0 +#define PALMAS_CLOCKS_CLK32K_KG_AUDIO 1 + +#endif /* __DT_BINDINGS_PALMAS_H */ -- 1.7.1.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html