diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
index 0e9c0d38b85c77eef348b7ff6b1738f5f10a4621..db362a96c38eb70d22524e10ed2bcf23b9b95f43 100644
--- a/drivers/acpi/acpi_lpss.c
+++ b/drivers/acpi/acpi_lpss.c
@@ -19,6 +19,7 @@
#include <linux/platform_device.h>
#include <linux/platform_data/clk-lpss.h>
#include <linux/pm_runtime.h>
+#include <linux/delay.h>
#include "internal.h"
@@ -28,6 +29,7 @@ ACPI_MODULE_NAME("acpi_lpss");
#define LPSS_LTR_SIZE 0x18
/* Offsets relative to LPSS_PRIVATE_OFFSET */
+#define LPSS_CLK_DIVIDER_DEF_MASK (BIT(1) | BIT(16))
#define LPSS_GENERAL 0x08
#define LPSS_GENERAL_LTR_MODE_SW BIT(2)
#define LPSS_GENERAL_UART_RTS_OVRD BIT(3)
@@ -43,6 +45,8 @@ ACPI_MODULE_NAME("acpi_lpss");
#define LPSS_TX_INT 0x20
#define LPSS_TX_INT_MASK BIT(1)
+#define LPSS_PRV_REG_COUNT 9
+
struct lpss_shared_clock {
const char *name;
unsigned long rate;
@@ -57,7 +61,9 @@ struct lpss_device_desc {
bool ltr_required;
unsigned int prv_offset;
size_t prv_size_override;
+ bool clk_divider;
bool clk_gate;
+ bool save_ctx;
struct lpss_shared_clock *shared_clock;
void (*setup)(struct lpss_private_data *pdata);
};
@@ -72,6 +78,7 @@ struct lpss_private_data {
resource_size_t mmio_size;
struct clk *clk;
const struct lpss_device_desc *dev_desc;
+ u32 prv_reg_ctx[LPSS_PRV_REG_COUNT];
};
static void lpss_uart_setup(struct lpss_private_data *pdata)
@@ -89,6 +96,14 @@ static void lpss_uart_setup(struct lpss_private_data *pdata)
}
static struct lpss_device_desc lpt_dev_desc = {
+ .clk_required = true,
+ .prv_offset = 0x800,
+ .ltr_required = true,
+ .clk_divider = true,
+ .clk_gate = true,
+};
+
+static struct lpss_device_desc lpt_i2c_dev_desc = {
.clk_required = true,
.prv_offset = 0x800,
.ltr_required = true,
@@ -99,6 +114,7 @@ static struct lpss_device_desc lpt_uart_dev_desc = {
.clk_required = true,
.prv_offset = 0x800,
.ltr_required = true,
+ .clk_divider = true,
.clk_gate = true,
.setup = lpss_uart_setup,
};
@@ -116,32 +132,25 @@ static struct lpss_shared_clock pwm_clock = {
static struct lpss_device_desc byt_pwm_dev_desc = {
.clk_required = true,
+ .save_ctx = true,
.shared_clock = &pwm_clock,
};
-static struct lpss_shared_clock uart_clock = {
- .name = "uart_clk",
- .rate = 44236800,
-};
-
static struct lpss_device_desc byt_uart_dev_desc = {
.clk_required = true,
.prv_offset = 0x800,
+ .clk_divider = true,
.clk_gate = true,
- .shared_clock = &uart_clock,
+ .save_ctx = true,
.setup = lpss_uart_setup,
};
-static struct lpss_shared_clock spi_clock = {
- .name = "spi_clk",
- .rate = 50000000,
-};
-
static struct lpss_device_desc byt_spi_dev_desc = {
.clk_required = true,
.prv_offset = 0x400,
+ .clk_divider = true,
.clk_gate = true,
- .shared_clock = &spi_clock,
+ .save_ctx = true,
};
static struct lpss_device_desc byt_sdio_dev_desc = {
@@ -156,6 +165,7 @@ static struct lpss_shared_clock i2c_clock = {
static struct lpss_device_desc byt_i2c_dev_desc = {
.clk_required = true,
.prv_offset = 0x800,
+ .save_ctx = true,
.shared_clock = &i2c_clock,
};
@@ -166,8 +176,8 @@ static const struct acpi_device_id acpi_lpss_device_ids[] = {
/* Lynxpoint LPSS devices */
{ "INT33C0", (unsigned long)&lpt_dev_desc },
{ "INT33C1", (unsigned long)&lpt_dev_desc },
- { "INT33C2", (unsigned long)&lpt_dev_desc },
- { "INT33C3", (unsigned long)&lpt_dev_desc },
+ { "INT33C2", (unsigned long)&lpt_i2c_dev_desc },
+ { "INT33C3", (unsigned long)&lpt_i2c_dev_desc },
{ "INT33C4", (unsigned long)&lpt_uart_dev_desc },
{ "INT33C5", (unsigned long)&lpt_uart_dev_desc },
{ "INT33C6", (unsigned long)&lpt_sdio_dev_desc },
@@ -183,8 +193,8 @@ static const struct acpi_device_id acpi_lpss_device_ids[] = {
{ "INT3430", (unsigned long)&lpt_dev_desc },
{ "INT3431", (unsigned long)&lpt_dev_desc },
- { "INT3432", (unsigned long)&lpt_dev_desc },
- { "INT3433", (unsigned long)&lpt_dev_desc },
+ { "INT3432", (unsigned long)&lpt_i2c_dev_desc },
+ { "INT3433", (unsigned long)&lpt_i2c_dev_desc },
{ "INT3434", (unsigned long)&lpt_uart_dev_desc },
{ "INT3435", (unsigned long)&lpt_uart_dev_desc },
{ "INT3436", (unsigned long)&lpt_sdio_dev_desc },
@@ -212,9 +222,11 @@ static int register_device_clock(struct acpi_device *adev,
{
const struct lpss_device_desc *dev_desc = pdata->dev_desc;
struct lpss_shared_clock *shared_clock = dev_desc->shared_clock;
+ const char *devname = dev_name(&adev->dev);
struct clk *clk = ERR_PTR(-ENODEV);
struct lpss_clk_data *clk_data;
- const char *parent;
+ const char *parent, *clk_name;
+ void __iomem *prv_base;
if (!lpss_clk_dev)
lpt_register_clock_device();
@@ -225,7 +237,7 @@ static int register_device_clock(struct acpi_device *adev,
if (dev_desc->clkdev_name) {
clk_register_clkdev(clk_data->clk, dev_desc->clkdev_name,
- dev_name(&adev->dev));
+ devname);
return 0;
}
@@ -234,6 +246,7 @@ static int register_device_clock(struct acpi_device *adev,
return -ENODATA;
parent = clk_data->name;
+ prv_base = pdata->mmio_base + dev_desc->prv_offset;
if (shared_clock) {
clk = shared_clock->clk;
@@ -247,16 +260,41 @@ static int register_device_clock(struct acpi_device *adev,
}
if (dev_desc->clk_gate) {
- clk = clk_register_gate(NULL, dev_name(&adev->dev), parent, 0,
- pdata->mmio_base + dev_desc->prv_offset,
- 0, 0, NULL);
- pdata->clk = clk;
+ clk = clk_register_gate(NULL, devname, parent, 0,
+ prv_base, 0, 0, NULL);
+ parent = devname;
+ }
+
+ if (dev_desc->clk_divider) {
+ /* Prevent division by zero */
+ if (!readl(prv_base))
+ writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
+
+ clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
+ if (!clk_name)
+ return -ENOMEM;
+ clk = clk_register_fractional_divider(NULL, clk_name, parent,
+ 0, prv_base,
+ 1, 15, 16, 15, 0, NULL);
+ parent = clk_name;
+
+ clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
+ if (!clk_name) {
+ kfree(parent);
+ return -ENOMEM;
+ }
+ clk = clk_register_gate(NULL, clk_name, parent,
+ CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
+ prv_base, 31, 0, NULL);
+ kfree(parent);
+ kfree(clk_name);
}
if (IS_ERR(clk))
return PTR_ERR(clk);
- clk_register_clkdev(clk, NULL, dev_name(&adev->dev));
+ pdata->clk = clk;
+ clk_register_clkdev(clk, NULL, devname);
return 0;
}
@@ -454,6 +492,126 @@ static void acpi_lpss_set_ltr(struct device *dev, s32 val)
}
}
+#ifdef CONFIG_PM
+/**
+ * acpi_lpss_save_ctx() - Save the private registers of LPSS device
+ * @dev: LPSS device
+ *
+ * Most LPSS devices have private registers which may loose their context when
+ * the device is powered down. acpi_lpss_save_ctx() saves those registers into
+ * prv_reg_ctx array.
+ */
+static void acpi_lpss_save_ctx(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ unsigned int i;
+
+ for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
+ unsigned long offset = i * sizeof(u32);
+
+ pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
+ dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
+ pdata->prv_reg_ctx[i], offset);
+ }
+}
+
+/**
+ * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
+ * @dev: LPSS device
+ *
+ * Restores the registers that were previously stored with acpi_lpss_save_ctx().
+ */
+static void acpi_lpss_restore_ctx(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ unsigned int i;
+
+ /*
+ * The following delay is needed or the subsequent write operations may
+ * fail. The LPSS devices are actually PCI devices and the PCI spec
+ * expects 10ms delay before the device can be accessed after D3 to D0
+ * transition.
+ */
+ msleep(10);
+
+ for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
+ unsigned long offset = i * sizeof(u32);
+
+ __lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
+ dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
+ pdata->prv_reg_ctx[i], offset);
+ }
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int acpi_lpss_suspend_late(struct device *dev)
+{
+ int ret = pm_generic_suspend_late(dev);
+
+ if (ret)
+ return ret;
+
+ acpi_lpss_save_ctx(dev);
+ return acpi_dev_suspend_late(dev);
+}
+
+static int acpi_lpss_restore_early(struct device *dev)
+{
+ int ret = acpi_dev_resume_early(dev);
+
+ if (ret)
+ return ret;
+
+ acpi_lpss_restore_ctx(dev);
+ return pm_generic_resume_early(dev);
+}
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM_RUNTIME
+static int acpi_lpss_runtime_suspend(struct device *dev)
+{
+ int ret = pm_generic_runtime_suspend(dev);
+
+ if (ret)
+ return ret;
+
+ acpi_lpss_save_ctx(dev);
+ return acpi_dev_runtime_suspend(dev);
+}
+
+static int acpi_lpss_runtime_resume(struct device *dev)
+{
+ int ret = acpi_dev_runtime_resume(dev);
+
+ if (ret)
+ return ret;
+
+ acpi_lpss_restore_ctx(dev);
+ return pm_generic_runtime_resume(dev);
+}
+#endif /* CONFIG_PM_RUNTIME */
+#endif /* CONFIG_PM */
+
+static struct dev_pm_domain acpi_lpss_pm_domain = {
+ .ops = {
+#ifdef CONFIG_PM_SLEEP
+ .suspend_late = acpi_lpss_suspend_late,
+ .restore_early = acpi_lpss_restore_early,
+ .prepare = acpi_subsys_prepare,
+ .complete = acpi_subsys_complete,
+ .suspend = acpi_subsys_suspend,
+ .resume_early = acpi_subsys_resume_early,
+ .freeze = acpi_subsys_freeze,
+ .poweroff = acpi_subsys_suspend,
+ .poweroff_late = acpi_subsys_suspend_late,
+#endif
+#ifdef CONFIG_PM_RUNTIME
+ .runtime_suspend = acpi_lpss_runtime_suspend,
+ .runtime_resume = acpi_lpss_runtime_resume,
+#endif
+ },
+};
+
static int acpi_lpss_platform_notify(struct notifier_block *nb,
unsigned long action, void *data)
{
@@ -461,7 +619,6 @@ static int acpi_lpss_platform_notify(struct notifier_block *nb,
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)
@@ -471,7 +628,7 @@ static int acpi_lpss_platform_notify(struct notifier_block *nb,
return 0;
pdata = acpi_driver_data(adev);
- if (!pdata || !pdata->mmio_base || !pdata->dev_desc->ltr_required)
+ if (!pdata || !pdata->mmio_base)
return 0;
if (pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
@@ -479,12 +636,27 @@ static int acpi_lpss_platform_notify(struct notifier_block *nb,
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);
+ switch (action) {
+ case BUS_NOTIFY_BOUND_DRIVER:
+ if (pdata->dev_desc->save_ctx)
+ pdev->dev.pm_domain = &acpi_lpss_pm_domain;
+ break;
+ case BUS_NOTIFY_UNBOUND_DRIVER:
+ if (pdata->dev_desc->save_ctx)
+ pdev->dev.pm_domain = NULL;
+ break;
+ case BUS_NOTIFY_ADD_DEVICE:
+ if (pdata->dev_desc->ltr_required)
+ return sysfs_create_group(&pdev->dev.kobj,
+ &lpss_attr_group);
+ case BUS_NOTIFY_DEL_DEVICE:
+ if (pdata->dev_desc->ltr_required)
+ sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
+ default:
+ break;
+ }
- return ret;
+ return 0;
}
static struct notifier_block acpi_lpss_nb = {