arch/x86/kernel/pmc_atom.c - kernel/hikey-linaro - Git at Google

 /*
  * Intel Atom SOC Power Management Controller Driver
  * Copyright (c) 2014, Intel Corporation.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
  * version 2, as published by the Free Software Foundation.
  *
  * This program is distributed in the hope 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.
  *
  */

 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/pci.h>
 #include <linux/device.h>
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/io.h>

 #include <asm/pmc_atom.h>

 struct pmc_dev {
 	u32 base_addr;
 	void __iomem *regmap;
 #ifdef CONFIG_DEBUG_FS
 	struct dentry *dbgfs_dir;
 #endif /* CONFIG_DEBUG_FS */
 };

 static struct pmc_dev pmc_device;
 static u32 acpi_base_addr;

 struct pmc_bit_map {
 	const char *name;
 	u32 bit_mask;
 };

 static const struct pmc_bit_map dev_map[] = {
 	{"0  - LPSS1_F0_DMA",		BIT_LPSS1_F0_DMA},
 	{"1  - LPSS1_F1_PWM1",		BIT_LPSS1_F1_PWM1},
 	{"2  - LPSS1_F2_PWM2",		BIT_LPSS1_F2_PWM2},
 	{"3  - LPSS1_F3_HSUART1",	BIT_LPSS1_F3_HSUART1},
 	{"4  - LPSS1_F4_HSUART2",	BIT_LPSS1_F4_HSUART2},
 	{"5  - LPSS1_F5_SPI",		BIT_LPSS1_F5_SPI},
 	{"6  - LPSS1_F6_Reserved",	BIT_LPSS1_F6_XXX},
 	{"7  - LPSS1_F7_Reserved",	BIT_LPSS1_F7_XXX},
 	{"8  - SCC_EMMC",		BIT_SCC_EMMC},
 	{"9  - SCC_SDIO",		BIT_SCC_SDIO},
 	{"10 - SCC_SDCARD",		BIT_SCC_SDCARD},
 	{"11 - SCC_MIPI",		BIT_SCC_MIPI},
 	{"12 - HDA",			BIT_HDA},
 	{"13 - LPE",			BIT_LPE},
 	{"14 - OTG",			BIT_OTG},
 	{"15 - USH",			BIT_USH},
 	{"16 - GBE",			BIT_GBE},
 	{"17 - SATA",			BIT_SATA},
 	{"18 - USB_EHCI",		BIT_USB_EHCI},
 	{"19 - SEC",			BIT_SEC},
 	{"20 - PCIE_PORT0",		BIT_PCIE_PORT0},
 	{"21 - PCIE_PORT1",		BIT_PCIE_PORT1},
 	{"22 - PCIE_PORT2",		BIT_PCIE_PORT2},
 	{"23 - PCIE_PORT3",		BIT_PCIE_PORT3},
 	{"24 - LPSS2_F0_DMA",		BIT_LPSS2_F0_DMA},
 	{"25 - LPSS2_F1_I2C1",		BIT_LPSS2_F1_I2C1},
 	{"26 - LPSS2_F2_I2C2",		BIT_LPSS2_F2_I2C2},
 	{"27 - LPSS2_F3_I2C3",		BIT_LPSS2_F3_I2C3},
 	{"28 - LPSS2_F3_I2C4",		BIT_LPSS2_F4_I2C4},
 	{"29 - LPSS2_F5_I2C5",		BIT_LPSS2_F5_I2C5},
 	{"30 - LPSS2_F6_I2C6",		BIT_LPSS2_F6_I2C6},
 	{"31 - LPSS2_F7_I2C7",		BIT_LPSS2_F7_I2C7},
 	{"32 - SMB",			BIT_SMB},
 	{"33 - OTG_SS_PHY",		BIT_OTG_SS_PHY},
 	{"34 - USH_SS_PHY",		BIT_USH_SS_PHY},
 	{"35 - DFX",			BIT_DFX},
 };

 static const struct pmc_bit_map pss_map[] = {
 	{"0  - GBE",			PMC_PSS_BIT_GBE},
 	{"1  - SATA",			PMC_PSS_BIT_SATA},
 	{"2  - HDA",			PMC_PSS_BIT_HDA},
 	{"3  - SEC",			PMC_PSS_BIT_SEC},
 	{"4  - PCIE",			PMC_PSS_BIT_PCIE},
 	{"5  - LPSS",			PMC_PSS_BIT_LPSS},
 	{"6  - LPE",			PMC_PSS_BIT_LPE},
 	{"7  - DFX",			PMC_PSS_BIT_DFX},
 	{"8  - USH_CTRL",		PMC_PSS_BIT_USH_CTRL},
 	{"9  - USH_SUS",		PMC_PSS_BIT_USH_SUS},
 	{"10 - USH_VCCS",		PMC_PSS_BIT_USH_VCCS},
 	{"11 - USH_VCCA",		PMC_PSS_BIT_USH_VCCA},
 	{"12 - OTG_CTRL",		PMC_PSS_BIT_OTG_CTRL},
 	{"13 - OTG_VCCS",		PMC_PSS_BIT_OTG_VCCS},
 	{"14 - OTG_VCCA_CLK",		PMC_PSS_BIT_OTG_VCCA_CLK},
 	{"15 - OTG_VCCA",		PMC_PSS_BIT_OTG_VCCA},
 	{"16 - USB",			PMC_PSS_BIT_USB},
 	{"17 - USB_SUS",		PMC_PSS_BIT_USB_SUS},
 };

 static inline u32 pmc_reg_read(struct pmc_dev *pmc, int reg_offset)
 {
 	return readl(pmc->regmap + reg_offset);
 }

 static inline void pmc_reg_write(struct pmc_dev *pmc, int reg_offset, u32 val)
 {
 	writel(val, pmc->regmap + reg_offset);
 }

 static void pmc_power_off(void)
 {
 	u16	pm1_cnt_port;
 	u32	pm1_cnt_value;

 	pr_info("Preparing to enter system sleep state S5\n");

 	pm1_cnt_port = acpi_base_addr + PM1_CNT;

 	pm1_cnt_value = inl(pm1_cnt_port);
 	pm1_cnt_value &= SLEEP_TYPE_MASK;
 	pm1_cnt_value |= SLEEP_TYPE_S5;
 	pm1_cnt_value |= SLEEP_ENABLE;

 	outl(pm1_cnt_value, pm1_cnt_port);
 }

 static void pmc_hw_reg_setup(struct pmc_dev *pmc)
 {
 	/*
 	 * Disable PMC S0IX_WAKE_EN events coming from:
 	 * - LPC clock run
 	 * - GPIO_SUS ored dedicated IRQs
 	 * - GPIO_SCORE ored dedicated IRQs
 	 * - GPIO_SUS shared IRQ
 	 * - GPIO_SCORE shared IRQ
 	 */
 	pmc_reg_write(pmc, PMC_S0IX_WAKE_EN, (u32)PMC_WAKE_EN_SETTING);
 }

 #ifdef CONFIG_DEBUG_FS
 static int pmc_dev_state_show(struct seq_file *s, void *unused)
 {
 	struct pmc_dev *pmc = s->private;
 	u32 func_dis, func_dis_2, func_dis_index;
 	u32 d3_sts_0, d3_sts_1, d3_sts_index;
 	int dev_num, dev_index, reg_index;

 	func_dis = pmc_reg_read(pmc, PMC_FUNC_DIS);
 	func_dis_2 = pmc_reg_read(pmc, PMC_FUNC_DIS_2);
 	d3_sts_0 = pmc_reg_read(pmc, PMC_D3_STS_0);
 	d3_sts_1 = pmc_reg_read(pmc, PMC_D3_STS_1);

 	dev_num = ARRAY_SIZE(dev_map);

 	for (dev_index = 0; dev_index < dev_num; dev_index++) {
 		reg_index = dev_index / PMC_REG_BIT_WIDTH;
 		if (reg_index) {
 			func_dis_index = func_dis_2;
 			d3_sts_index = d3_sts_1;
 		} else {
 			func_dis_index = func_dis;
 			d3_sts_index = d3_sts_0;
 		}

 		seq_printf(s, "Dev: %-32s\tState: %s [%s]\n",
 			dev_map[dev_index].name,
 			dev_map[dev_index].bit_mask & func_dis_index ?
 			"Disabled" : "Enabled ",
 			dev_map[dev_index].bit_mask & d3_sts_index ?
 			"D3" : "D0");
 	}
 	return 0;
 }

 static int pmc_dev_state_open(struct inode *inode, struct file *file)
 {
 	return single_open(file, pmc_dev_state_show, inode->i_private);
 }

 static const struct file_operations pmc_dev_state_ops = {
 	.open		= pmc_dev_state_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };

 static int pmc_pss_state_show(struct seq_file *s, void *unused)
 {
 	struct pmc_dev *pmc = s->private;
 	u32 pss = pmc_reg_read(pmc, PMC_PSS);
 	int pss_index;

 	for (pss_index = 0; pss_index < ARRAY_SIZE(pss_map); pss_index++) {
 		seq_printf(s, "Island: %-32s\tState: %s\n",
 			pss_map[pss_index].name,
 			pss_map[pss_index].bit_mask & pss ? "Off" : "On");
 	}
 	return 0;
 }

 static int pmc_pss_state_open(struct inode *inode, struct file *file)
 {
 	return single_open(file, pmc_pss_state_show, inode->i_private);
 }

 static const struct file_operations pmc_pss_state_ops = {
 	.open		= pmc_pss_state_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };

 static int pmc_sleep_tmr_show(struct seq_file *s, void *unused)
 {
 	struct pmc_dev *pmc = s->private;
 	u64 s0ir_tmr, s0i1_tmr, s0i2_tmr, s0i3_tmr, s0_tmr;

 	s0ir_tmr = (u64)pmc_reg_read(pmc, PMC_S0IR_TMR) << PMC_TMR_SHIFT;
 	s0i1_tmr = (u64)pmc_reg_read(pmc, PMC_S0I1_TMR) << PMC_TMR_SHIFT;
 	s0i2_tmr = (u64)pmc_reg_read(pmc, PMC_S0I2_TMR) << PMC_TMR_SHIFT;
 	s0i3_tmr = (u64)pmc_reg_read(pmc, PMC_S0I3_TMR) << PMC_TMR_SHIFT;
 	s0_tmr = (u64)pmc_reg_read(pmc, PMC_S0_TMR) << PMC_TMR_SHIFT;

 	seq_printf(s, "S0IR Residency:\t%lldus\n", s0ir_tmr);
 	seq_printf(s, "S0I1 Residency:\t%lldus\n", s0i1_tmr);
 	seq_printf(s, "S0I2 Residency:\t%lldus\n", s0i2_tmr);
 	seq_printf(s, "S0I3 Residency:\t%lldus\n", s0i3_tmr);
 	seq_printf(s, "S0   Residency:\t%lldus\n", s0_tmr);
 	return 0;
 }

 static int pmc_sleep_tmr_open(struct inode *inode, struct file *file)
 {
 	return single_open(file, pmc_sleep_tmr_show, inode->i_private);
 }

 static const struct file_operations pmc_sleep_tmr_ops = {
 	.open		= pmc_sleep_tmr_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };

 static void pmc_dbgfs_unregister(struct pmc_dev *pmc)
 {
 	debugfs_remove_recursive(pmc->dbgfs_dir);
 }

 static int pmc_dbgfs_register(struct pmc_dev *pmc, struct pci_dev *pdev)
 {
 	struct dentry *dir, *f;

 	dir = debugfs_create_dir("pmc_atom", NULL);
 	if (!dir)
 		return -ENOMEM;

 	pmc->dbgfs_dir = dir;

 	f = debugfs_create_file("dev_state", S_IFREG | S_IRUGO,
 				dir, pmc, &pmc_dev_state_ops);
 	if (!f) {
 		dev_err(&pdev->dev, "dev_state register failed\n");
 		goto err;
 	}

 	f = debugfs_create_file("pss_state", S_IFREG | S_IRUGO,
 				dir, pmc, &pmc_pss_state_ops);
 	if (!f) {
 		dev_err(&pdev->dev, "pss_state register failed\n");
 		goto err;
 	}

 	f = debugfs_create_file("sleep_state", S_IFREG | S_IRUGO,
 				dir, pmc, &pmc_sleep_tmr_ops);
 	if (!f) {
 		dev_err(&pdev->dev, "sleep_state register failed\n");
 		goto err;
 	}

 	return 0;
 err:
 	pmc_dbgfs_unregister(pmc);
 	return -ENODEV;
 }
 #else
 static int pmc_dbgfs_register(struct pmc_dev *pmc, struct pci_dev *pdev)
 {
 	return 0;
 }
 #endif /* CONFIG_DEBUG_FS */

 static int pmc_setup_dev(struct pci_dev *pdev)
 {
 	struct pmc_dev *pmc = &pmc_device;
 	int ret;

 	/* Obtain ACPI base address */
 	pci_read_config_dword(pdev, ACPI_BASE_ADDR_OFFSET, &acpi_base_addr);
 	acpi_base_addr &= ACPI_BASE_ADDR_MASK;

 	/* Install power off function */
 	if (acpi_base_addr != 0 && pm_power_off == NULL)
 		pm_power_off = pmc_power_off;

 	pci_read_config_dword(pdev, PMC_BASE_ADDR_OFFSET, &pmc->base_addr);
 	pmc->base_addr &= PMC_BASE_ADDR_MASK;

 	pmc->regmap = ioremap_nocache(pmc->base_addr, PMC_MMIO_REG_LEN);
 	if (!pmc->regmap) {
 		dev_err(&pdev->dev, "error: ioremap failed\n");
 		return -ENOMEM;
 	}

 	/* PMC hardware registers setup */
 	pmc_hw_reg_setup(pmc);

 	ret = pmc_dbgfs_register(pmc, pdev);
 	if (ret) {
 		iounmap(pmc->regmap);
 	}

 	return ret;
 }

 /*
  * Data for PCI driver interface
  *
  * This data only exists for exporting the supported
  * PCI ids via MODULE_DEVICE_TABLE.  We do not actually
  * register a pci_driver, because lpc_ich will register
  * a driver on the same PCI id.
  */
 static const struct pci_device_id pmc_pci_ids[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_VLV_PMC) },
 	{ 0, },
 };

 MODULE_DEVICE_TABLE(pci, pmc_pci_ids);

 static int __init pmc_atom_init(void)
 {
 	struct pci_dev *pdev = NULL;
 	const struct pci_device_id *ent;

 	/* We look for our device - PCU PMC
 	 * we assume that there is max. one device.
 	 *
 	 * We can't use plain pci_driver mechanism,
 	 * as the device is really a multiple function device,
 	 * main driver that binds to the pci_device is lpc_ich
 	 * and have to find & bind to the device this way.
 	 */
 	for_each_pci_dev(pdev) {
 		ent = pci_match_id(pmc_pci_ids, pdev);
 		if (ent)
 			return pmc_setup_dev(pdev);
 	}
 	/* Device not found. */
 	return -ENODEV;
 }

 module_init(pmc_atom_init);
 /* no module_exit, this driver shouldn't be unloaded */

 MODULE_AUTHOR("Aubrey Li <aubrey.li@linux.intel.com>");
 MODULE_DESCRIPTION("Intel Atom SOC Power Management Controller Interface");
 MODULE_LICENSE("GPL v2");
	/*
	* Intel Atom SOC Power Management Controller Driver
	* Copyright (c) 2014, Intel Corporation.
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms and conditions of the GNU General Public License,
	* version 2, as published by the Free Software Foundation.
	*
	* This program is distributed in the hope 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.
	*
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/pci.h>
	#include <linux/device.h>
	#include <linux/debugfs.h>
	#include <linux/seq_file.h>
	#include <linux/io.h>

	#include <asm/pmc_atom.h>

	struct pmc_dev {
	u32 base_addr;
	void __iomem *regmap;
	#ifdef CONFIG_DEBUG_FS
	struct dentry *dbgfs_dir;
	#endif /* CONFIG_DEBUG_FS */
	};

	static struct pmc_dev pmc_device;
	static u32 acpi_base_addr;

	struct pmc_bit_map {
	const char *name;
	u32 bit_mask;
	};

	static const struct pmc_bit_map dev_map[] = {
	{"0 - LPSS1_F0_DMA", BIT_LPSS1_F0_DMA},
	{"1 - LPSS1_F1_PWM1", BIT_LPSS1_F1_PWM1},
	{"2 - LPSS1_F2_PWM2", BIT_LPSS1_F2_PWM2},
	{"3 - LPSS1_F3_HSUART1", BIT_LPSS1_F3_HSUART1},
	{"4 - LPSS1_F4_HSUART2", BIT_LPSS1_F4_HSUART2},
	{"5 - LPSS1_F5_SPI", BIT_LPSS1_F5_SPI},
	{"6 - LPSS1_F6_Reserved", BIT_LPSS1_F6_XXX},
	{"7 - LPSS1_F7_Reserved", BIT_LPSS1_F7_XXX},
	{"8 - SCC_EMMC", BIT_SCC_EMMC},
	{"9 - SCC_SDIO", BIT_SCC_SDIO},
	{"10 - SCC_SDCARD", BIT_SCC_SDCARD},
	{"11 - SCC_MIPI", BIT_SCC_MIPI},
	{"12 - HDA", BIT_HDA},
	{"13 - LPE", BIT_LPE},
	{"14 - OTG", BIT_OTG},
	{"15 - USH", BIT_USH},
	{"16 - GBE", BIT_GBE},
	{"17 - SATA", BIT_SATA},
	{"18 - USB_EHCI", BIT_USB_EHCI},
	{"19 - SEC", BIT_SEC},
	{"20 - PCIE_PORT0", BIT_PCIE_PORT0},
	{"21 - PCIE_PORT1", BIT_PCIE_PORT1},
	{"22 - PCIE_PORT2", BIT_PCIE_PORT2},
	{"23 - PCIE_PORT3", BIT_PCIE_PORT3},
	{"24 - LPSS2_F0_DMA", BIT_LPSS2_F0_DMA},
	{"25 - LPSS2_F1_I2C1", BIT_LPSS2_F1_I2C1},
	{"26 - LPSS2_F2_I2C2", BIT_LPSS2_F2_I2C2},
	{"27 - LPSS2_F3_I2C3", BIT_LPSS2_F3_I2C3},
	{"28 - LPSS2_F3_I2C4", BIT_LPSS2_F4_I2C4},
	{"29 - LPSS2_F5_I2C5", BIT_LPSS2_F5_I2C5},
	{"30 - LPSS2_F6_I2C6", BIT_LPSS2_F6_I2C6},
	{"31 - LPSS2_F7_I2C7", BIT_LPSS2_F7_I2C7},
	{"32 - SMB", BIT_SMB},
	{"33 - OTG_SS_PHY", BIT_OTG_SS_PHY},
	{"34 - USH_SS_PHY", BIT_USH_SS_PHY},
	{"35 - DFX", BIT_DFX},
	};

	static const struct pmc_bit_map pss_map[] = {
	{"0 - GBE", PMC_PSS_BIT_GBE},
	{"1 - SATA", PMC_PSS_BIT_SATA},
	{"2 - HDA", PMC_PSS_BIT_HDA},
	{"3 - SEC", PMC_PSS_BIT_SEC},
	{"4 - PCIE", PMC_PSS_BIT_PCIE},
	{"5 - LPSS", PMC_PSS_BIT_LPSS},
	{"6 - LPE", PMC_PSS_BIT_LPE},
	{"7 - DFX", PMC_PSS_BIT_DFX},
	{"8 - USH_CTRL", PMC_PSS_BIT_USH_CTRL},
	{"9 - USH_SUS", PMC_PSS_BIT_USH_SUS},
	{"10 - USH_VCCS", PMC_PSS_BIT_USH_VCCS},
	{"11 - USH_VCCA", PMC_PSS_BIT_USH_VCCA},
	{"12 - OTG_CTRL", PMC_PSS_BIT_OTG_CTRL},
	{"13 - OTG_VCCS", PMC_PSS_BIT_OTG_VCCS},
	{"14 - OTG_VCCA_CLK", PMC_PSS_BIT_OTG_VCCA_CLK},
	{"15 - OTG_VCCA", PMC_PSS_BIT_OTG_VCCA},
	{"16 - USB", PMC_PSS_BIT_USB},
	{"17 - USB_SUS", PMC_PSS_BIT_USB_SUS},
	};

	static inline u32 pmc_reg_read(struct pmc_dev *pmc, int reg_offset)
	{
	return readl(pmc->regmap + reg_offset);
	}

	static inline void pmc_reg_write(struct pmc_dev *pmc, int reg_offset, u32 val)
	{
	writel(val, pmc->regmap + reg_offset);
	}

	static void pmc_power_off(void)
	{
	u16 pm1_cnt_port;
	u32 pm1_cnt_value;

	pr_info("Preparing to enter system sleep state S5\n");

	pm1_cnt_port = acpi_base_addr + PM1_CNT;

	pm1_cnt_value = inl(pm1_cnt_port);
	pm1_cnt_value &= SLEEP_TYPE_MASK;
	pm1_cnt_value \|= SLEEP_TYPE_S5;
	pm1_cnt_value \|= SLEEP_ENABLE;

	outl(pm1_cnt_value, pm1_cnt_port);
	}

	static void pmc_hw_reg_setup(struct pmc_dev *pmc)
	{
	/*
	* Disable PMC S0IX_WAKE_EN events coming from:
	* - LPC clock run
	* - GPIO_SUS ored dedicated IRQs
	* - GPIO_SCORE ored dedicated IRQs
	* - GPIO_SUS shared IRQ
	* - GPIO_SCORE shared IRQ
	*/
	pmc_reg_write(pmc, PMC_S0IX_WAKE_EN, (u32)PMC_WAKE_EN_SETTING);
	}

	#ifdef CONFIG_DEBUG_FS
	static int pmc_dev_state_show(struct seq_file s, void unused)
	{
	struct pmc_dev *pmc = s->private;
	u32 func_dis, func_dis_2, func_dis_index;
	u32 d3_sts_0, d3_sts_1, d3_sts_index;
	int dev_num, dev_index, reg_index;

	func_dis = pmc_reg_read(pmc, PMC_FUNC_DIS);
	func_dis_2 = pmc_reg_read(pmc, PMC_FUNC_DIS_2);
	d3_sts_0 = pmc_reg_read(pmc, PMC_D3_STS_0);
	d3_sts_1 = pmc_reg_read(pmc, PMC_D3_STS_1);

	dev_num = ARRAY_SIZE(dev_map);

	for (dev_index = 0; dev_index < dev_num; dev_index++) {
	reg_index = dev_index / PMC_REG_BIT_WIDTH;
	if (reg_index) {
	func_dis_index = func_dis_2;
	d3_sts_index = d3_sts_1;
	} else {
	func_dis_index = func_dis;
	d3_sts_index = d3_sts_0;
	}

	seq_printf(s, "Dev: %-32s\tState: %s [%s]\n",
	dev_map[dev_index].name,
	dev_map[dev_index].bit_mask & func_dis_index ?
	"Disabled" : "Enabled ",
	dev_map[dev_index].bit_mask & d3_sts_index ?
	"D3" : "D0");
	}
	return 0;
	}

	static int pmc_dev_state_open(struct inode inode, struct file file)
	{
	return single_open(file, pmc_dev_state_show, inode->i_private);
	}

	static const struct file_operations pmc_dev_state_ops = {
	.open = pmc_dev_state_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	};

	static int pmc_pss_state_show(struct seq_file s, void unused)
	{
	struct pmc_dev *pmc = s->private;
	u32 pss = pmc_reg_read(pmc, PMC_PSS);
	int pss_index;

	for (pss_index = 0; pss_index < ARRAY_SIZE(pss_map); pss_index++) {
	seq_printf(s, "Island: %-32s\tState: %s\n",
	pss_map[pss_index].name,
	pss_map[pss_index].bit_mask & pss ? "Off" : "On");
	}
	return 0;
	}

	static int pmc_pss_state_open(struct inode inode, struct file file)
	{
	return single_open(file, pmc_pss_state_show, inode->i_private);
	}

	static const struct file_operations pmc_pss_state_ops = {
	.open = pmc_pss_state_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	};

	static int pmc_sleep_tmr_show(struct seq_file s, void unused)
	{
	struct pmc_dev *pmc = s->private;
	u64 s0ir_tmr, s0i1_tmr, s0i2_tmr, s0i3_tmr, s0_tmr;

	s0ir_tmr = (u64)pmc_reg_read(pmc, PMC_S0IR_TMR) << PMC_TMR_SHIFT;
	s0i1_tmr = (u64)pmc_reg_read(pmc, PMC_S0I1_TMR) << PMC_TMR_SHIFT;
	s0i2_tmr = (u64)pmc_reg_read(pmc, PMC_S0I2_TMR) << PMC_TMR_SHIFT;
	s0i3_tmr = (u64)pmc_reg_read(pmc, PMC_S0I3_TMR) << PMC_TMR_SHIFT;
	s0_tmr = (u64)pmc_reg_read(pmc, PMC_S0_TMR) << PMC_TMR_SHIFT;

	seq_printf(s, "S0IR Residency:\t%lldus\n", s0ir_tmr);
	seq_printf(s, "S0I1 Residency:\t%lldus\n", s0i1_tmr);
	seq_printf(s, "S0I2 Residency:\t%lldus\n", s0i2_tmr);
	seq_printf(s, "S0I3 Residency:\t%lldus\n", s0i3_tmr);
	seq_printf(s, "S0 Residency:\t%lldus\n", s0_tmr);
	return 0;
	}

	static int pmc_sleep_tmr_open(struct inode inode, struct file file)
	{
	return single_open(file, pmc_sleep_tmr_show, inode->i_private);
	}

	static const struct file_operations pmc_sleep_tmr_ops = {
	.open = pmc_sleep_tmr_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	};

	static void pmc_dbgfs_unregister(struct pmc_dev *pmc)
	{
	debugfs_remove_recursive(pmc->dbgfs_dir);
	}

	static int pmc_dbgfs_register(struct pmc_dev pmc, struct pci_dev pdev)
	{
	struct dentry dir, f;

	dir = debugfs_create_dir("pmc_atom", NULL);
	if (!dir)
	return -ENOMEM;

	pmc->dbgfs_dir = dir;

	f = debugfs_create_file("dev_state", S_IFREG \| S_IRUGO,
	dir, pmc, &pmc_dev_state_ops);
	if (!f) {
	dev_err(&pdev->dev, "dev_state register failed\n");
	goto err;
	}

	f = debugfs_create_file("pss_state", S_IFREG \| S_IRUGO,
	dir, pmc, &pmc_pss_state_ops);
	if (!f) {
	dev_err(&pdev->dev, "pss_state register failed\n");
	goto err;
	}

	f = debugfs_create_file("sleep_state", S_IFREG \| S_IRUGO,
	dir, pmc, &pmc_sleep_tmr_ops);
	if (!f) {
	dev_err(&pdev->dev, "sleep_state register failed\n");
	goto err;
	}

	return 0;
	err:
	pmc_dbgfs_unregister(pmc);
	return -ENODEV;
	}
	#else
	static int pmc_dbgfs_register(struct pmc_dev pmc, struct pci_dev pdev)
	{
	return 0;
	}
	#endif /* CONFIG_DEBUG_FS */

	static int pmc_setup_dev(struct pci_dev *pdev)
	{
	struct pmc_dev *pmc = &pmc_device;
	int ret;

	/* Obtain ACPI base address */
	pci_read_config_dword(pdev, ACPI_BASE_ADDR_OFFSET, &acpi_base_addr);
	acpi_base_addr &= ACPI_BASE_ADDR_MASK;

	/* Install power off function */
	if (acpi_base_addr != 0 && pm_power_off == NULL)
	pm_power_off = pmc_power_off;

	pci_read_config_dword(pdev, PMC_BASE_ADDR_OFFSET, &pmc->base_addr);
	pmc->base_addr &= PMC_BASE_ADDR_MASK;

	pmc->regmap = ioremap_nocache(pmc->base_addr, PMC_MMIO_REG_LEN);
	if (!pmc->regmap) {
	dev_err(&pdev->dev, "error: ioremap failed\n");
	return -ENOMEM;
	}

	/* PMC hardware registers setup */
	pmc_hw_reg_setup(pmc);

	ret = pmc_dbgfs_register(pmc, pdev);
	if (ret) {
	iounmap(pmc->regmap);
	}

	return ret;
	}

	/*
	* Data for PCI driver interface
	*
	* This data only exists for exporting the supported
	* PCI ids via MODULE_DEVICE_TABLE. We do not actually
	* register a pci_driver, because lpc_ich will register
	* a driver on the same PCI id.
	*/
	static const struct pci_device_id pmc_pci_ids[] = {
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_VLV_PMC) },
	{ 0, },
	};

	MODULE_DEVICE_TABLE(pci, pmc_pci_ids);

	static int __init pmc_atom_init(void)
	{
	struct pci_dev *pdev = NULL;
	const struct pci_device_id *ent;

	/* We look for our device - PCU PMC
	* we assume that there is max. one device.
	*
	* We can't use plain pci_driver mechanism,
	* as the device is really a multiple function device,
	* main driver that binds to the pci_device is lpc_ich
	* and have to find & bind to the device this way.
	*/
	for_each_pci_dev(pdev) {
	ent = pci_match_id(pmc_pci_ids, pdev);
	if (ent)
	return pmc_setup_dev(pdev);
	}
	/* Device not found. */
	return -ENODEV;
	}

	module_init(pmc_atom_init);
	/* no module_exit, this driver shouldn't be unloaded */

	MODULE_AUTHOR("Aubrey Li <aubrey.li@linux.intel.com>");
	MODULE_DESCRIPTION("Intel Atom SOC Power Management Controller Interface");
	MODULE_LICENSE("GPL v2");