diff options
Diffstat (limited to 'kernel/drivers/clk/ti/clk-dra7-atl.c')
-rw-r--r-- | kernel/drivers/clk/ti/clk-dra7-atl.c | 317 |
1 files changed, 317 insertions, 0 deletions
diff --git a/kernel/drivers/clk/ti/clk-dra7-atl.c b/kernel/drivers/clk/ti/clk-dra7-atl.c new file mode 100644 index 000000000..d86bc46b9 --- /dev/null +++ b/kernel/drivers/clk/ti/clk-dra7-atl.c @@ -0,0 +1,317 @@ +/* + * DRA7 ATL (Audio Tracking Logic) clock driver + * + * Copyright (C) 2013 Texas Instruments, Inc. + * + * Peter Ujfalusi <peter.ujfalusi@ti.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * 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. + */ + +#include <linux/module.h> +#include <linux/clk-provider.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> + +#define DRA7_ATL_INSTANCES 4 + +#define DRA7_ATL_PPMR_REG(id) (0x200 + (id * 0x80)) +#define DRA7_ATL_BBSR_REG(id) (0x204 + (id * 0x80)) +#define DRA7_ATL_ATLCR_REG(id) (0x208 + (id * 0x80)) +#define DRA7_ATL_SWEN_REG(id) (0x210 + (id * 0x80)) +#define DRA7_ATL_BWSMUX_REG(id) (0x214 + (id * 0x80)) +#define DRA7_ATL_AWSMUX_REG(id) (0x218 + (id * 0x80)) +#define DRA7_ATL_PCLKMUX_REG(id) (0x21c + (id * 0x80)) + +#define DRA7_ATL_SWEN BIT(0) +#define DRA7_ATL_DIVIDER_MASK (0x1f) +#define DRA7_ATL_PCLKMUX BIT(0) +struct dra7_atl_clock_info; + +struct dra7_atl_desc { + struct clk *clk; + struct clk_hw hw; + struct dra7_atl_clock_info *cinfo; + int id; + + bool probed; /* the driver for the IP has been loaded */ + bool valid; /* configured */ + bool enabled; + u32 bws; /* Baseband Word Select Mux */ + u32 aws; /* Audio Word Select Mux */ + u32 divider; /* Cached divider value */ +}; + +struct dra7_atl_clock_info { + struct device *dev; + void __iomem *iobase; + + struct dra7_atl_desc *cdesc; +}; + +#define to_atl_desc(_hw) container_of(_hw, struct dra7_atl_desc, hw) + +static inline void atl_write(struct dra7_atl_clock_info *cinfo, u32 reg, + u32 val) +{ + __raw_writel(val, cinfo->iobase + reg); +} + +static inline int atl_read(struct dra7_atl_clock_info *cinfo, u32 reg) +{ + return __raw_readl(cinfo->iobase + reg); +} + +static int atl_clk_enable(struct clk_hw *hw) +{ + struct dra7_atl_desc *cdesc = to_atl_desc(hw); + + if (!cdesc->probed) + goto out; + + if (unlikely(!cdesc->valid)) + dev_warn(cdesc->cinfo->dev, "atl%d has not been configured\n", + cdesc->id); + pm_runtime_get_sync(cdesc->cinfo->dev); + + atl_write(cdesc->cinfo, DRA7_ATL_ATLCR_REG(cdesc->id), + cdesc->divider - 1); + atl_write(cdesc->cinfo, DRA7_ATL_SWEN_REG(cdesc->id), DRA7_ATL_SWEN); + +out: + cdesc->enabled = true; + + return 0; +} + +static void atl_clk_disable(struct clk_hw *hw) +{ + struct dra7_atl_desc *cdesc = to_atl_desc(hw); + + if (!cdesc->probed) + goto out; + + atl_write(cdesc->cinfo, DRA7_ATL_SWEN_REG(cdesc->id), 0); + pm_runtime_put_sync(cdesc->cinfo->dev); + +out: + cdesc->enabled = false; +} + +static int atl_clk_is_enabled(struct clk_hw *hw) +{ + struct dra7_atl_desc *cdesc = to_atl_desc(hw); + + return cdesc->enabled; +} + +static unsigned long atl_clk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct dra7_atl_desc *cdesc = to_atl_desc(hw); + + return parent_rate / cdesc->divider; +} + +static long atl_clk_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + unsigned divider; + + divider = (*parent_rate + rate / 2) / rate; + if (divider > DRA7_ATL_DIVIDER_MASK + 1) + divider = DRA7_ATL_DIVIDER_MASK + 1; + + return *parent_rate / divider; +} + +static int atl_clk_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct dra7_atl_desc *cdesc; + u32 divider; + + if (!hw || !rate) + return -EINVAL; + + cdesc = to_atl_desc(hw); + divider = ((parent_rate + rate / 2) / rate) - 1; + if (divider > DRA7_ATL_DIVIDER_MASK) + divider = DRA7_ATL_DIVIDER_MASK; + + cdesc->divider = divider + 1; + + return 0; +} + +const struct clk_ops atl_clk_ops = { + .enable = atl_clk_enable, + .disable = atl_clk_disable, + .is_enabled = atl_clk_is_enabled, + .recalc_rate = atl_clk_recalc_rate, + .round_rate = atl_clk_round_rate, + .set_rate = atl_clk_set_rate, +}; + +static void __init of_dra7_atl_clock_setup(struct device_node *node) +{ + struct dra7_atl_desc *clk_hw = NULL; + struct clk_init_data init = { 0 }; + const char **parent_names = NULL; + struct clk *clk; + + clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL); + if (!clk_hw) { + pr_err("%s: could not allocate dra7_atl_desc\n", __func__); + return; + } + + clk_hw->hw.init = &init; + clk_hw->divider = 1; + init.name = node->name; + init.ops = &atl_clk_ops; + init.flags = CLK_IGNORE_UNUSED; + init.num_parents = of_clk_get_parent_count(node); + + if (init.num_parents != 1) { + pr_err("%s: atl clock %s must have 1 parent\n", __func__, + node->name); + goto cleanup; + } + + parent_names = kzalloc(sizeof(char *), GFP_KERNEL); + + if (!parent_names) + goto cleanup; + + parent_names[0] = of_clk_get_parent_name(node, 0); + + init.parent_names = parent_names; + + clk = clk_register(NULL, &clk_hw->hw); + + if (!IS_ERR(clk)) { + of_clk_add_provider(node, of_clk_src_simple_get, clk); + kfree(parent_names); + return; + } +cleanup: + kfree(parent_names); + kfree(clk_hw); +} +CLK_OF_DECLARE(dra7_atl_clock, "ti,dra7-atl-clock", of_dra7_atl_clock_setup); + +static int of_dra7_atl_clk_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct dra7_atl_clock_info *cinfo; + int i; + int ret = 0; + + if (!node) + return -ENODEV; + + cinfo = devm_kzalloc(&pdev->dev, sizeof(*cinfo), GFP_KERNEL); + if (!cinfo) + return -ENOMEM; + + cinfo->iobase = of_iomap(node, 0); + cinfo->dev = &pdev->dev; + pm_runtime_enable(cinfo->dev); + pm_runtime_irq_safe(cinfo->dev); + + pm_runtime_get_sync(cinfo->dev); + atl_write(cinfo, DRA7_ATL_PCLKMUX_REG(0), DRA7_ATL_PCLKMUX); + + for (i = 0; i < DRA7_ATL_INSTANCES; i++) { + struct device_node *cfg_node; + char prop[5]; + struct dra7_atl_desc *cdesc; + struct of_phandle_args clkspec; + struct clk *clk; + int rc; + + rc = of_parse_phandle_with_args(node, "ti,provided-clocks", + NULL, i, &clkspec); + + if (rc) { + pr_err("%s: failed to lookup atl clock %d\n", __func__, + i); + return -EINVAL; + } + + clk = of_clk_get_from_provider(&clkspec); + + cdesc = to_atl_desc(__clk_get_hw(clk)); + cdesc->cinfo = cinfo; + cdesc->id = i; + + /* Get configuration for the ATL instances */ + snprintf(prop, sizeof(prop), "atl%u", i); + cfg_node = of_find_node_by_name(node, prop); + if (cfg_node) { + ret = of_property_read_u32(cfg_node, "bws", + &cdesc->bws); + ret |= of_property_read_u32(cfg_node, "aws", + &cdesc->aws); + if (!ret) { + cdesc->valid = true; + atl_write(cinfo, DRA7_ATL_BWSMUX_REG(i), + cdesc->bws); + atl_write(cinfo, DRA7_ATL_AWSMUX_REG(i), + cdesc->aws); + } + } + + cdesc->probed = true; + /* + * Enable the clock if it has been asked prior to loading the + * hw driver + */ + if (cdesc->enabled) + atl_clk_enable(__clk_get_hw(clk)); + } + pm_runtime_put_sync(cinfo->dev); + + return ret; +} + +static int of_dra7_atl_clk_remove(struct platform_device *pdev) +{ + pm_runtime_disable(&pdev->dev); + + return 0; +} + +static const struct of_device_id of_dra7_atl_clk_match_tbl[] = { + { .compatible = "ti,dra7-atl", }, + {}, +}; +MODULE_DEVICE_TABLE(of, of_dra7_atl_clk_match_tbl); + +static struct platform_driver dra7_atl_clk_driver = { + .driver = { + .name = "dra7-atl", + .of_match_table = of_dra7_atl_clk_match_tbl, + }, + .probe = of_dra7_atl_clk_probe, + .remove = of_dra7_atl_clk_remove, +}; + +module_platform_driver(dra7_atl_clk_driver); + +MODULE_DESCRIPTION("Clock driver for DRA7 Audio Tracking Logic"); +MODULE_ALIAS("platform:dra7-atl-clock"); +MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>"); +MODULE_LICENSE("GPL v2"); |