diff options
Diffstat (limited to 'arch/arm/mach-mx51/lpmodes.c')
-rw-r--r-- | arch/arm/mach-mx51/lpmodes.c | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/arch/arm/mach-mx51/lpmodes.c b/arch/arm/mach-mx51/lpmodes.c new file mode 100644 index 000000000000..32af9ccc4f6a --- /dev/null +++ b/arch/arm/mach-mx51/lpmodes.c @@ -0,0 +1,309 @@ +/* + * Copyright 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +/*! + * @file mx51_lpmodes.c + * + * @brief Driver for the Freescale Semiconductor MXC low power modes setup. + * + * MX51 is designed to play and video with minimal power consumption. + * This driver enables the platform to enter and exit audio and video low + * power modes. + * + * @ingroup PM + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/fs.h> +#include <linux/interrupt.h> +#include <linux/jiffies.h> +#include <linux/device.h> +#include <linux/delay.h> +#include <linux/clk.h> +#include <linux/workqueue.h> +#include <linux/platform_device.h> +#include <mach/clock.h> +#include <mach/hardware.h> +#include <linux/regulator/machine.h> +#include "crm_regs.h" + +#define ARM_LP_CLK 166250000 +#define GP_LPM_VOLTAGE 775000 +#define GP_NORMAL_VOLTAGE 1050000 + +static int org_cpu_rate; +int lp_video_mode; +int lp_audio_mode; +static struct device *lpmode_dev; +struct regulator *gp_core; + +void enter_lp_video_mode(void) +{ +} + +void exit_lp_video_mode(void) +{ +} + +void enter_lp_audio_mode(void) +{ + struct clk *tclk; + int ret; + + struct clk *p_clk; + struct clk *amode_parent_clk; + + + tclk = clk_get(NULL, "ipu_clk"); + if (clk_get_usecount(tclk) != 0) { + printk(KERN_INFO + "Cannot enter AUDIO LPM mode - display is still active\n"); + return; + } + + tclk = clk_get(NULL, "cpu_clk"); + org_cpu_rate = clk_get_rate(tclk); + +#ifdef CHANGE_DDR2_TO_PLL2 + tclk = clk_get(NULL, "ddr_clk"); + clk_set_parent(tclk, clk_get(NULL, "axi_a_clk")); + + /* Set CPU clock to be derived from PLL2 instead of PLL1 */ + tclk = clk_get(NULL, "pll1_sw_clk"); + clk_set_parent(tclk, clk_get(NULL, "pll2")); + clk_enable(tclk); + + tclk = clk_get(NULL, "ddr_clk"); + clk_set_parent(tclk, clk_get(NULL, "ddr_hf_clk")); +#endif + + /*Change the DDR freq to 133Mhz. */ + tclk = clk_get(NULL, "ddr_hf_clk"); + clk_set_rate(tclk, clk_round_rate(tclk, 133000000)); + + tclk = clk_get(NULL, "cpu_clk"); + ret = clk_set_rate(tclk, ARM_LP_CLK); + if (ret != 0) + printk(KERN_DEBUG "cannot set CPU clock rate\n"); + clk_put(tclk); + /* Set the voltage to 0.775v for the GP domain. */ + ret = regulator_set_voltage(gp_core, GP_LPM_VOLTAGE, GP_LPM_VOLTAGE); + if (ret < 0) + printk(KERN_DEBUG "COULD NOT SET GP VOLTAGE!!!\n"); + + tclk = clk_get(NULL, "periph_apm_clk"); + amode_parent_clk = clk_get(NULL, "lp_apm"); + p_clk = clk_get_parent(tclk); + /* Make sure osc_clk is the parent of lp_apm. */ + clk_set_parent(amode_parent_clk, clk_get(NULL, "osc")); + /* Set the parent of periph_apm_clk to be lp_apm */ + clk_set_parent(tclk, amode_parent_clk); + + amode_parent_clk = tclk; + + tclk = clk_get(NULL, "main_bus_clk"); + p_clk = clk_get_parent(tclk); + /* Set the parent of main_bus_clk to be periph_apm_clk */ + clk_set_parent(tclk, amode_parent_clk); + + clk_set_rate(clk_get(NULL, "axi_a_clk"), 24000000); + clk_set_rate(clk_get(NULL, "axi_b_clk"), 24000000); + clk_set_rate(clk_get(NULL, "ahb_clk"), 24000000); + clk_set_rate(clk_get(NULL, "emi_slow_clk"), 24000000); + clk_set_rate(clk_get(NULL, "nfc_clk"), 12000000); + + /* disable PLL3 */ + tclk = clk_get(NULL, "pll3"); + if (tclk->usecount == 1) + clk_disable(tclk); + + /* disable PLL2 */ + tclk = clk_get(NULL, "pll2"); + if (tclk->usecount == 1) + clk_disable(tclk); + + /* disable PLL1 */ + tclk = clk_get(NULL, "pll1_main_clk"); + if (tclk->usecount == 1) + clk_disable(tclk); + + lp_audio_mode = 1; +} + +void exit_lp_audio_mode(void) +{ + struct clk *tclk; + struct clk *p_clk; + struct clk *rmode_parent_clk; + int ret; + + /* Set the voltage to 1.05v for the GP domain. */ + ret = regulator_set_voltage(gp_core, + GP_NORMAL_VOLTAGE, GP_NORMAL_VOLTAGE); + if (ret < 0) + printk(KERN_DEBUG "COULD NOT SET GP VOLTAGE!!!\n"); + + rmode_parent_clk = clk_get(NULL, "pll2"); + clk_enable(rmode_parent_clk); + + tclk = clk_get(NULL, "main_bus_clk"); + p_clk = clk_get_parent(tclk); + + /* Set the dividers before setting the parent clock. */ + clk_set_rate(clk_get(NULL, "axi_a_clk"), 6000000); + clk_set_rate(clk_get(NULL, "axi_b_clk"), 4800000); + clk_set_rate(clk_get(NULL, "ahb_clk"), 4800000); + clk_set_rate(clk_get(NULL, "emi_slow_clk"), 4800000); + clk_set_rate(clk_get(NULL, "nfc_clk"), 1200000); + /* Set the parent of main_bus_clk to be pll2 */ + clk_set_parent(tclk, rmode_parent_clk); + +#ifdef CHANGE_DDR2_TO_PLL2 + tclk = clk_get(NULL, "ddr_clk"); + clk_set_parent(tclk, clk_get(NULL, "axi_a_clk")); + + /* Set CPU clock to be derived from PLL1 instead of PLL2 */ + tclk = clk_get(NULL, "pll1_sw_clk"); + clk_set_parent(tclk, clk_get(NULL, "pll1_main_clk")); + clk_disable(tclk); + + tclk = clk_get(NULL, "ddr_clk"); + clk_set_parent(tclk, clk_get(NULL, "ddr_hf_clk")); +#endif + + tclk = clk_get(NULL, "cpu_clk"); + ret = clk_set_rate(tclk, org_cpu_rate); + if (ret != 0) + printk(KERN_DEBUG "cannot set CPU clock rate\n"); + clk_put(tclk); + + tclk = clk_get(NULL, "cpu_clk"); + + ret = clk_set_rate(tclk, org_cpu_rate); + if (ret != 0) + printk(KERN_DEBUG "cannot set CPU clock rate\n"); + + + /*Change the DDR freq to 200MHz*/ + tclk = clk_get(NULL, "ddr_hf_clk"); + clk_set_rate(tclk, clk_round_rate(tclk, 200000000)); + lp_audio_mode = 0; + +} + +static ssize_t lp_curr_mode(struct device *dev, + struct device_attribute *attr, char *buf) +{ + if (lp_video_mode) + return sprintf(buf, "in lp_video_mode\n"); + else if (lp_audio_mode) + return sprintf(buf, "in lp_audio_mode\n"); + else + return sprintf(buf, "in normal mode\n"); +} + +static ssize_t set_lp_mode(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + printk(KERN_DEBUG "In set_lp_mode() \n"); + + if (strstr(buf, "enable_lp_video") != NULL) { + if (!lp_video_mode) + enter_lp_video_mode(); + } else if (strstr(buf, "disable_lp_video") != NULL) { + if (lp_video_mode) + exit_lp_video_mode(); + } else if (strstr(buf, "enable_lp_audio") != NULL) { + if (!lp_audio_mode) + enter_lp_audio_mode(); + } else if (strstr(buf, "disable_lp_audio") != NULL) { + if (lp_audio_mode) + exit_lp_audio_mode(); + } + return size; +} + +static DEVICE_ATTR(lp_modes, 0644, lp_curr_mode, set_lp_mode); + +/*! + * This is the probe routine for the lp_mode driver. + * + * @param pdev The platform device structure + * + * @return The function returns 0 on success + * + */ +static int __devinit mx51_lpmode_probe(struct platform_device *pdev) +{ + u32 res = 0; + lpmode_dev = &pdev->dev; + + res = sysfs_create_file(&lpmode_dev->kobj, &dev_attr_lp_modes.attr); + if (res) { + printk(KERN_ERR + "lpmode_dev: Unable to register sysdev entry for lpmode_dev"); + return res; + } + + if (res != 0) { + printk(KERN_ERR "lpmode_dev: Unable to start"); + return res; + } + gp_core = regulator_get(NULL, "SW1"); + lp_video_mode = 0; + lp_audio_mode = 0; + + return 0; +} + +static struct platform_driver mx51_lpmode_driver = { + .driver = { + .name = "mx51_lpmode", + }, + .probe = mx51_lpmode_probe, +}; + +/*! + * Initialise the mx51_lpmode_driver. + * + * @return The function always returns 0. + */ + +static int __init lpmode_init(void) +{ + if (platform_driver_register(&mx51_lpmode_driver) != 0) { + printk(KERN_ERR "mx37_lpmode_driver register failed\n"); + return -ENODEV; + } + + printk(KERN_INFO "LPMode driver module loaded\n"); + return 0; +} + +static void __exit lpmode_cleanup(void) +{ + sysfs_remove_file(&lpmode_dev->kobj, &dev_attr_lp_modes.attr); + + /* Unregister the device structure */ + platform_driver_unregister(&mx51_lpmode_driver); +} + +module_init(lpmode_init); +module_exit(lpmode_cleanup); + +MODULE_AUTHOR("Freescale Semiconductor, Inc."); +MODULE_DESCRIPTION("LPMode driver"); +MODULE_LICENSE("GPL"); |