diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-lpss_ltr | 44 | ||||
| -rw-r--r-- | drivers/acpi/acpi_lpss.c | 139 |
2 files changed, 178 insertions, 5 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-lpss_ltr b/Documentation/ABI/testing/sysfs-devices-lpss_ltr new file mode 100644 index 000000000000..ea9298d9bbaf --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-lpss_ltr @@ -0,0 +1,44 @@ +What: /sys/devices/.../lpss_ltr/ +Date: March 2013 +Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> +Description: + The /sys/devices/.../lpss_ltr/ directory is only present for + devices included into the Intel Lynxpoint Low Power Subsystem + (LPSS). If present, it contains attributes containing the LTR + mode and the values of LTR registers of the device. + +What: /sys/devices/.../lpss_ltr/ltr_mode +Date: March 2013 +Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> +Description: + The /sys/devices/.../lpss_ltr/ltr_mode attribute contains an + integer number (0 or 1) indicating whether or not the devices' + LTR functionality is working in the software mode (1). + + This attribute is read-only. If the device's runtime PM status + is not "active", attempts to read from this attribute cause + -EAGAIN to be returned. + +What: /sys/devices/.../lpss_ltr/auto_ltr +Date: March 2013 +Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> +Description: + The /sys/devices/.../lpss_ltr/auto_ltr attribute contains the + current value of the device's AUTO_LTR register (raw) + represented as an 8-digit hexadecimal number. + + This attribute is read-only. If the device's runtime PM status + is not "active", attempts to read from this attribute cause + -EAGAIN to be returned. + +What: /sys/devices/.../lpss_ltr/sw_ltr +Date: March 2013 +Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> +Description: + The /sys/devices/.../lpss_ltr/auto_ltr attribute contains the + current value of the device's SW_LTR register (raw) represented + as an 8-digit hexadecimal number. + + This attribute is read-only. If the device's runtime PM status + is not "active", attempts to read from this attribute cause + -EAGAIN to be returned. diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c index 823df46a3deb..c87db0e47d09 100644 --- a/drivers/acpi/acpi_lpss.c +++ b/drivers/acpi/acpi_lpss.c @@ -18,17 +18,26 @@ #include <linux/io.h> #include <linux/platform_device.h> #include <linux/platform_data/clk-lpss.h> +#include <linux/pm_runtime.h> #include "internal.h" ACPI_MODULE_NAME("acpi_lpss"); -#define LPSS_CLK_OFFSET 0x800 #define LPSS_CLK_SIZE 0x04 +#define LPSS_LTR_SIZE 0x18 + +/* Offsets relative to LPSS_PRIVATE_OFFSET */ +#define LPSS_GENERAL 0x08 +#define LPSS_GENERAL_LTR_MODE_SW BIT(2) +#define LPSS_SW_LTR 0x10 +#define LPSS_AUTO_LTR 0x14 struct lpss_device_desc { bool clk_required; const char *clk_parent; + bool ltr_required; + unsigned int prv_offset; }; struct lpss_private_data { @@ -41,6 +50,13 @@ struct lpss_private_data { static struct lpss_device_desc lpt_dev_desc = { .clk_required = true, .clk_parent = "lpss_clk", + .prv_offset = 0x800, + .ltr_required = true, +}; + +static struct lpss_device_desc lpt_sdio_dev_desc = { + .prv_offset = 0x1000, + .ltr_required = true, }; static const struct acpi_device_id acpi_lpss_device_ids[] = { @@ -51,7 +67,7 @@ static const struct acpi_device_id acpi_lpss_device_ids[] = { { "INT33C3", (unsigned long)&lpt_dev_desc }, { "INT33C4", (unsigned long)&lpt_dev_desc }, { "INT33C5", (unsigned long)&lpt_dev_desc }, - { "INT33C6", }, + { "INT33C6", (unsigned long)&lpt_sdio_dev_desc }, { "INT33C7", }, { } @@ -80,12 +96,12 @@ static int register_device_clock(struct acpi_device *adev, lpt_register_clock_device(); if (!dev_desc->clk_parent || !pdata->mmio_base - || pdata->mmio_size < LPSS_CLK_OFFSET + LPSS_CLK_SIZE) + || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE) return -ENODATA; pdata->clk = clk_register_gate(NULL, dev_name(&adev->dev), dev_desc->clk_parent, 0, - pdata->mmio_base + LPSS_CLK_OFFSET, + pdata->mmio_base + dev_desc->prv_offset, 0, 0, NULL); if (IS_ERR(pdata->clk)) return PTR_ERR(pdata->clk); @@ -151,6 +167,117 @@ static int acpi_lpss_create_device(struct acpi_device *adev, return ret; } +static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val) +{ + struct acpi_device *adev; + struct lpss_private_data *pdata; + unsigned long flags; + int ret; + + ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev); + if (WARN_ON(ret)) + return ret; + + spin_lock_irqsave(&dev->power.lock, flags); + if (pm_runtime_suspended(dev)) { + ret = -EAGAIN; + goto out; + } + pdata = acpi_driver_data(adev); + if (WARN_ON(!pdata || !pdata->mmio_base)) { + ret = -ENODEV; + goto out; + } + *val = readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg); + + out: + spin_unlock_irqrestore(&dev->power.lock, flags); + return ret; +} + +static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + u32 ltr_value = 0; + unsigned int reg; + int ret; + + reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR; + ret = lpss_reg_read(dev, reg, <r_value); + if (ret) + return ret; + + return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value); +} + +static ssize_t lpss_ltr_mode_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + u32 ltr_mode = 0; + char *outstr; + int ret; + + ret = lpss_reg_read(dev, LPSS_GENERAL, <r_mode); + if (ret) + return ret; + + outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto"; + return sprintf(buf, "%s\n", outstr); +} + +static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL); +static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL); +static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL); + +static struct attribute *lpss_attrs[] = { + &dev_attr_auto_ltr.attr, + &dev_attr_sw_ltr.attr, + &dev_attr_ltr_mode.attr, + NULL, +}; + +static struct attribute_group lpss_attr_group = { + .attrs = lpss_attrs, + .name = "lpss_ltr", +}; + +static int acpi_lpss_platform_notify(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct platform_device *pdev = to_platform_device(data); + struct lpss_private_data *pdata; + struct acpi_device *adev; + const struct acpi_device_id *id; + int ret = 0; + + id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev); + if (!id || !id->driver_data) + return 0; + + if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev)) + return 0; + + pdata = acpi_driver_data(adev); + if (!pdata || !pdata->mmio_base || !pdata->dev_desc->ltr_required) + return 0; + + if (pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) { + dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n"); + return 0; + } + + if (action == BUS_NOTIFY_ADD_DEVICE) + ret = sysfs_create_group(&pdev->dev.kobj, &lpss_attr_group); + else if (action == BUS_NOTIFY_DEL_DEVICE) + sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group); + + return ret; +} + +static struct notifier_block acpi_lpss_nb = { + .notifier_call = acpi_lpss_platform_notify, +}; + static struct acpi_scan_handler lpss_handler = { .ids = acpi_lpss_device_ids, .attach = acpi_lpss_create_device, @@ -158,6 +285,8 @@ static struct acpi_scan_handler lpss_handler = { void __init acpi_lpss_init(void) { - if (!lpt_clk_init()) + if (!lpt_clk_init()) { + bus_register_notifier(&platform_bus_type, &acpi_lpss_nb); acpi_scan_add_handler(&lpss_handler); + } } |