soc: qcom: qpnp-pbs: Add PBS driver support
The PBS driver helps the client drivers to trigger the PBS
event to execute the PBS RAM configuration as requested by the
client driver.
Change-Id: Ic5d1290ffa0b66ac7a8f68529aafcf0b871ee3e8
Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index cf715e5..0f8d9b6 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -214,6 +214,15 @@
deadlocks. It does not run during the bootup process, so it will
not catch any early lockups.
+config QPNP_PBS
+ tristate "PBS trigger support for QPNP PMIC"
+ depends on SPMI
+ help
+ This driver supports configuring software PBS trigger event through PBS
+ RAM on Qualcomm Technologies, Inc. QPNP PMICs. This module provides
+ the APIs to the client drivers that wants to send the PBS trigger
+ event to the PBS RAM.
+
config QCOM_MEMORY_DUMP_V2
bool "QCOM Memory Dump V2 Support"
help
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index 45384668..00a1284 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -3,6 +3,7 @@
obj-$(CONFIG_QCOM_LLCC) += llcc-core.o llcc-slice.o
obj-$(CONFIG_QCOM_SDM845_LLCC) += llcc-sdm845.o
obj-$(CONFIG_QCOM_LLCC_AMON) += llcc-amon.o
+obj-$(CONFIG_QPNP_PBS) += qpnp-pbs.o
obj-$(CONFIG_QCOM_PM) += spm.o
obj-$(CONFIG_QCOM_SMD) += smd.o
obj-$(CONFIG_QCOM_SMD_RPM) += smd-rpm.o
diff --git a/drivers/soc/qcom/qpnp-pbs.c b/drivers/soc/qcom/qpnp-pbs.c
new file mode 100644
index 0000000..287c8a2
--- /dev/null
+++ b/drivers/soc/qcom/qpnp-pbs.c
@@ -0,0 +1,361 @@
+/* Copyright (c) 2017, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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) "PBS: %s: " fmt, __func__
+
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/spmi.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/qpnp/qpnp-pbs.h>
+
+#define QPNP_PBS_DEV_NAME "qcom,qpnp-pbs"
+
+#define PBS_CLIENT_TRIG_CTL 0x42
+#define PBS_CLIENT_SW_TRIG_BIT BIT(7)
+#define PBS_CLIENT_SCRATCH1 0x50
+#define PBS_CLIENT_SCRATCH2 0x51
+
+static LIST_HEAD(pbs_dev_list);
+static DEFINE_MUTEX(pbs_list_lock);
+
+struct qpnp_pbs {
+ struct platform_device *pdev;
+ struct device *dev;
+ struct device_node *dev_node;
+ struct regmap *regmap;
+ struct mutex pbs_lock;
+ struct list_head link;
+
+ u32 base;
+};
+
+static int qpnp_pbs_read(struct qpnp_pbs *pbs, u32 address,
+ u8 *val, int count)
+{
+ int rc = 0;
+ struct platform_device *pdev = pbs->pdev;
+
+ rc = regmap_bulk_read(pbs->regmap, address, val, count);
+ if (rc)
+ pr_err("Failed to read address=0x%02x sid=0x%02x rc=%d\n",
+ address, to_spmi_device(pdev->dev.parent)->usid, rc);
+
+ return rc;
+}
+
+static int qpnp_pbs_write(struct qpnp_pbs *pbs, u16 address,
+ u8 *val, int count)
+{
+ int rc = 0;
+ struct platform_device *pdev = pbs->pdev;
+
+ rc = regmap_bulk_write(pbs->regmap, address, val, count);
+ if (rc < 0)
+ pr_err("Failed to write address =0x%02x sid=0x%02x rc=%d\n",
+ address, to_spmi_device(pdev->dev.parent)->usid, rc);
+ else
+ pr_debug("Wrote 0x%02X to addr 0x%04x\n", *val, address);
+
+ return rc;
+}
+
+static int qpnp_pbs_masked_write(struct qpnp_pbs *pbs, u16 address,
+ u8 mask, u8 val)
+{
+ int rc;
+
+ rc = regmap_update_bits(pbs->regmap, address, mask, val);
+ if (rc < 0)
+ pr_err("Failed to write address 0x%04X, rc = %d\n",
+ address, rc);
+ else
+ pr_debug("Wrote 0x%02X to addr 0x%04X\n",
+ val, address);
+
+ return rc;
+}
+
+static struct qpnp_pbs *get_pbs_client_node(struct device_node *dev_node)
+{
+ struct qpnp_pbs *pbs;
+
+ mutex_lock(&pbs_list_lock);
+ list_for_each_entry(pbs, &pbs_dev_list, link) {
+ if (dev_node == pbs->dev_node) {
+ mutex_unlock(&pbs_list_lock);
+ return pbs;
+ }
+ }
+
+ mutex_unlock(&pbs_list_lock);
+ return ERR_PTR(-EINVAL);
+}
+
+static int qpnp_pbs_wait_for_ack(struct qpnp_pbs *pbs, u8 bit_pos)
+{
+ int rc = 0;
+ u16 retries = 2000, dly = 1000;
+ u8 val;
+
+ while (retries--) {
+ rc = qpnp_pbs_read(pbs, pbs->base +
+ PBS_CLIENT_SCRATCH2, &val, 1);
+ if (rc < 0) {
+ pr_err("Failed to read register %x rc = %d\n",
+ PBS_CLIENT_SCRATCH2, rc);
+ return rc;
+ }
+
+ if (val == 0xFF) {
+ /* PBS error - clear SCRATCH2 register */
+ rc = qpnp_pbs_write(pbs, pbs->base +
+ PBS_CLIENT_SCRATCH2, 0, 1);
+ if (rc < 0) {
+ pr_err("Failed to clear register %x rc=%d\n",
+ PBS_CLIENT_SCRATCH2, rc);
+ return rc;
+ }
+
+ pr_err("NACK from PBS for bit %d\n", bit_pos);
+ return -EINVAL;
+ }
+
+ if (val & BIT(bit_pos)) {
+ pr_debug("PBS sequence for bit %d executed!\n",
+ bit_pos);
+ break;
+ }
+
+ usleep_range(dly, dly + 100);
+ }
+
+ if (!retries) {
+ pr_err("Timeout for PBS ACK/NACK for bit %d\n", bit_pos);
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+/**
+ * qpnp_pbs_trigger_event - Trigger the PBS RAM sequence
+ *
+ * Returns = 0 If the PBS RAM sequence executed successfully.
+ *
+ * Returns < 0 for errors.
+ *
+ * This function is used to trigger the PBS RAM sequence to be
+ * executed by the client driver.
+ *
+ * The PBS trigger sequence involves
+ * 1. setting the PBS sequence bit in PBS_CLIENT_SCRATCH1
+ * 2. Initiating the SW PBS trigger
+ * 3. Checking the equivalent bit in PBS_CLIENT_SCRATCH2 for the
+ * completion of the sequence.
+ * 4. If PBS_CLIENT_SCRATCH2 == 0xFF, the PBS sequence failed to execute
+ */
+int qpnp_pbs_trigger_event(struct device_node *dev_node, u8 bitmap)
+{
+ struct qpnp_pbs *pbs;
+ int rc = 0;
+ u16 bit_pos = 0;
+ u8 val, mask = 0;
+
+ if (!dev_node)
+ return -EINVAL;
+
+ if (!bitmap) {
+ pr_err("Invalid bitmap passed by client\n");
+ return -EINVAL;
+ }
+
+ pbs = get_pbs_client_node(dev_node);
+ if (IS_ERR_OR_NULL(pbs)) {
+ pr_err("Unable to find the PBS dev_node\n");
+ return -EINVAL;
+ }
+
+ mutex_lock(&pbs->pbs_lock);
+ rc = qpnp_pbs_read(pbs, pbs->base + PBS_CLIENT_SCRATCH2, &val, 1);
+ if (rc < 0) {
+ pr_err("read register %x failed rc = %d\n",
+ PBS_CLIENT_SCRATCH2, rc);
+ goto out;
+ }
+
+ if (val == 0xFF) {
+ /* PBS error - clear SCRATCH2 register */
+ rc = qpnp_pbs_write(pbs, pbs->base + PBS_CLIENT_SCRATCH2, 0, 1);
+ if (rc < 0) {
+ pr_err("Failed to clear register %x rc=%d\n",
+ PBS_CLIENT_SCRATCH2, rc);
+ goto out;
+ }
+ }
+
+ for (bit_pos = 0; bit_pos < 8; bit_pos++) {
+ if (bitmap & BIT(bit_pos)) {
+ /*
+ * Clear the PBS sequence bit position in
+ * PBS_CLIENT_SCRATCH2 mask register.
+ */
+ rc = qpnp_pbs_masked_write(pbs, pbs->base +
+ PBS_CLIENT_SCRATCH2, BIT(bit_pos), 0);
+ if (rc < 0) {
+ pr_err("Failed to clear %x reg bit rc=%d\n",
+ PBS_CLIENT_SCRATCH2, rc);
+ goto error;
+ }
+
+ /*
+ * Set the PBS sequence bit position in
+ * PBS_CLIENT_SCRATCH1 register.
+ */
+ val = mask = BIT(bit_pos);
+ rc = qpnp_pbs_masked_write(pbs, pbs->base +
+ PBS_CLIENT_SCRATCH1, mask, val);
+ if (rc < 0) {
+ pr_err("Failed to set %x reg bit rc=%d\n",
+ PBS_CLIENT_SCRATCH1, rc);
+ goto error;
+ }
+
+ /* Initiate the SW trigger */
+ val = mask = PBS_CLIENT_SW_TRIG_BIT;
+ rc = qpnp_pbs_masked_write(pbs, pbs->base +
+ PBS_CLIENT_TRIG_CTL, mask, val);
+ if (rc < 0) {
+ pr_err("Failed to write register %x rc=%d\n",
+ PBS_CLIENT_TRIG_CTL, rc);
+ goto error;
+ }
+
+ rc = qpnp_pbs_wait_for_ack(pbs, bit_pos);
+ if (rc < 0) {
+ pr_err("Error during wait_for_ack\n");
+ goto error;
+ }
+
+ /*
+ * Clear the PBS sequence bit position in
+ * PBS_CLIENT_SCRATCH1 register.
+ */
+ rc = qpnp_pbs_masked_write(pbs, pbs->base +
+ PBS_CLIENT_SCRATCH1, BIT(bit_pos), 0);
+ if (rc < 0) {
+ pr_err("Failed to clear %x reg bit rc=%d\n",
+ PBS_CLIENT_SCRATCH1, rc);
+ goto error;
+ }
+
+ /*
+ * Clear the PBS sequence bit position in
+ * PBS_CLIENT_SCRATCH2 mask register.
+ */
+ rc = qpnp_pbs_masked_write(pbs, pbs->base +
+ PBS_CLIENT_SCRATCH2, BIT(bit_pos), 0);
+ if (rc < 0) {
+ pr_err("Failed to clear %x reg bit rc=%d\n",
+ PBS_CLIENT_SCRATCH2, rc);
+ goto error;
+ }
+
+ }
+ }
+
+error:
+ /* Clear all the requested bitmap */
+ rc = qpnp_pbs_masked_write(pbs, pbs->base + PBS_CLIENT_SCRATCH1,
+ bitmap, 0);
+ if (rc < 0)
+ pr_err("Failed to clear %x reg bit rc=%d\n",
+ PBS_CLIENT_SCRATCH1, rc);
+out:
+ mutex_unlock(&pbs->pbs_lock);
+
+ return rc;
+}
+EXPORT_SYMBOL(qpnp_pbs_trigger_event);
+
+static int qpnp_pbs_probe(struct platform_device *pdev)
+{
+ int rc = 0;
+ u32 val = 0;
+ struct qpnp_pbs *pbs;
+
+ pbs = devm_kzalloc(&pdev->dev, sizeof(*pbs), GFP_KERNEL);
+ if (!pbs)
+ return -ENOMEM;
+
+ pbs->pdev = pdev;
+ pbs->dev = &pdev->dev;
+ pbs->dev_node = pdev->dev.of_node;
+ pbs->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!pbs->regmap) {
+ dev_err(&pdev->dev, "Couldn't get parent's regmap\n");
+ return -EINVAL;
+ }
+
+ rc = of_property_read_u32(pdev->dev.of_node, "reg", &val);
+ if (rc < 0) {
+ dev_err(&pdev->dev,
+ "Couldn't find reg in node = %s rc = %d\n",
+ pdev->dev.of_node->full_name, rc);
+ return rc;
+ }
+
+ pbs->base = val;
+ mutex_init(&pbs->pbs_lock);
+
+ dev_set_drvdata(&pdev->dev, pbs);
+
+ mutex_lock(&pbs_list_lock);
+ list_add(&pbs->link, &pbs_dev_list);
+ mutex_unlock(&pbs_list_lock);
+
+ return 0;
+}
+
+static const struct of_device_id qpnp_pbs_match_table[] = {
+ { .compatible = QPNP_PBS_DEV_NAME },
+ {}
+};
+
+static struct platform_driver qpnp_pbs_driver = {
+ .driver = {
+ .name = QPNP_PBS_DEV_NAME,
+ .owner = THIS_MODULE,
+ .of_match_table = qpnp_pbs_match_table,
+ },
+ .probe = qpnp_pbs_probe,
+};
+
+static int __init qpnp_pbs_init(void)
+{
+ return platform_driver_register(&qpnp_pbs_driver);
+}
+arch_initcall(qpnp_pbs_init);
+
+static void __exit qpnp_pbs_exit(void)
+{
+ return platform_driver_unregister(&qpnp_pbs_driver);
+}
+module_exit(qpnp_pbs_exit);
+
+MODULE_DESCRIPTION("QPNP PBS DRIVER");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" QPNP_PBS_DEV_NAME);