[PATCH v2 06/11] mfd: qcom-smd-rpm: Driver for the Qualcomm RPM over SMD

bjorn
2015-06-26T21:53:17Z

From: Bjorn Andersson <bjorn.andersson@sonymobile.com>

Driver for the Resource Power Manager (RPM) found in Qualcomm 8974 based
devices.
The driver exposes resources that child drivers can operate on; to
implementing regulator, clock and bus frequency drivers.

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
---
drivers/mfd/Kconfig | 14 +++
drivers/mfd/Makefile | 1 +
drivers/mfd/qcom-smd-rpm.c | 236 +++++++++++++++++++++++++++++++++++++++
include/linux/mfd/qcom-smd-rpm.h | 35 ++++++
4 files changed, 286 insertions(+)
create mode 100644 drivers/mfd/qcom-smd-rpm.c
create mode 100644 include/linux/mfd/qcom-smd-rpm.h

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 6538159..666c812 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -656,6 +656,20 @@ config MFD_QCOM_RPM
Say M here if you want to include support for the Qualcomm RPM as a
module. This will build a module called "qcom_rpm".

+config MFD_QCOM_SMD_RPM
+ tristate "Qualcomm Resource Power Manager (RPM) over SMD"
+ depends on QCOM_SMD && OF
+ help
+ If you say yes to this option, support will be included for the
+ Resource Power Manager system found in the Qualcomm 8974 based
+ devices.
+
+ This is required to access many regulators, clocks and bus
+ frequencies controlled by the RPM on these devices.
+
+ Say M here if you want to include support for the Qualcomm RPM as a
+ module. This will build a module called "qcom-smd-rpm".
+
config MFD_SPMI_PMIC
tristate "Qualcomm SPMI PMICs"
depends on ARCH_QCOM || COMPILE_TEST
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index ea40e07..289bd24 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -156,6 +156,7 @@ obj-$(CONFIG_MFD_CS5535) += cs5535-mfd.o
obj-$(CONFIG_MFD_OMAP_USB_HOST) += omap-usb-host.o omap-usb-tll.o
obj-$(CONFIG_MFD_PM8921_CORE) += pm8921-core.o ssbi.o
obj-$(CONFIG_MFD_QCOM_RPM) += qcom_rpm.o
+obj-$(CONFIG_MFD_QCOM_SMD_RPM) += qcom-smd-rpm.o
obj-$(CONFIG_MFD_SPMI_PMIC) += qcom-spmi-pmic.o
obj-$(CONFIG_TPS65911_COMPARATOR) += tps65911-comparator.o
obj-$(CONFIG_MFD_TPS65090) += tps65090.o
diff --git a/drivers/mfd/qcom-smd-rpm.c b/drivers/mfd/qcom-smd-rpm.c
new file mode 100644
index 0000000..d6faf85
--- /dev/null
+++ b/drivers/mfd/qcom-smd-rpm.c
@@ -0,0 +1,236 @@
+/*
+ * Copyright (c) 2015, Sony Mobile Communications AB.
+ * Copyright (c) 2012-2013, 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.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of_platform.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+
+#include <linux/soc/qcom/smd.h>
+#include <linux/mfd/qcom-smd-rpm.h>
+
+#include <dt-bindings/mfd/qcom-smd-rpm.h>
+
+#define RPM_REQUEST_TIMEOUT (5 * HZ)
+
+/**
+ * struct qcom_smd_rpm - state of the rpm device driver
+ * @rpm_channel: reference to the smd channel
+ * @ack: completion for acks
+ * @lock: mutual exclusion around the send/complete pair
+ * @ack_status: result of the rpm request
+ */
+struct qcom_smd_rpm {
+ struct qcom_smd_channel *rpm_channel;
+
+ struct completion ack;
+ struct mutex lock;
+ int ack_status;
+};
+
+/**
+ * struct qcom_rpm_header - header for all rpm requests and responses
+ * @service_type: identifier of the service
+ * @length: length of the payload
+ */
+struct qcom_rpm_header {
+ u32 service_type;
+ u32 length;
+};
+
+/**
+ * struct qcom_rpm_request - request message to the rpm
+ * @msg_id: identifier of the outgoing message
+ * @flags: active/sleep state flags
+ * @type: resource type
+ * @id: resource id
+ * @data_len: length of the payload following this header
+ */
+struct qcom_rpm_request {
+ u32 msg_id;
+ u32 flags;
+ u32 type;
+ u32 id;
+ u32 data_len;
+};
+
+/**
+ * struct qcom_rpm_message - response message from the rpm
+ * @msg_type: indicator of the type of message
+ * @length: the size of this message, including the message header
+ * @msg_id: message id
+ * @message: textual message from the rpm
+ *
+ * Multiple of these messages can be stacked in an rpm message.
+ */
+struct qcom_rpm_message {
+ u32 msg_type;
+ u32 length;
+ union {
+ u32 msg_id;
+ u8 message[0];
+ };
+};
+
+#define RPM_SERVICE_TYPE_REQUEST 0x00716572 /* "req\0" */
+
+#define RPM_MSG_TYPE_ERR 0x00727265 /* "err\0" */
+#define RPM_MSG_TYPE_MSG_ID 0x2367736d /* "msg#" */
+
+/**
+ * qcom_rpm_smd_write - write @buf to @type:@id
+ * @rpm: rpm handle
+ * @type: resource type
+ * @id: resource identifier
+ * @buf: the data to be written
+ * @count: number of bytes in @buf
+ */
+int qcom_rpm_smd_write(struct qcom_smd_rpm *rpm,
+ int state,
+ u32 type, u32 id,
+ void *buf,
+ size_t count)
+{
+ static unsigned msg_id = 1;
+ int left;
+ int ret;
+
+ struct {
+ struct qcom_rpm_header hdr;
+ struct qcom_rpm_request req;
+ u8 payload[count];
+ } pkt;
+
+ /* SMD packets to the RPM may not exceed 256 bytes */
+ if (WARN_ON(sizeof(pkt) >= 256))
+ return -EINVAL;
+
+ mutex_lock(&rpm->lock);
+
+ pkt.hdr.service_type = RPM_SERVICE_TYPE_REQUEST;
+ pkt.hdr.length = sizeof(struct qcom_rpm_request) + count;
+
+ pkt.req.msg_id = msg_id++;
+ pkt.req.flags = BIT(state);
+ pkt.req.type = type;
+ pkt.req.id = id;
+ pkt.req.data_len = count;
+ memcpy(pkt.payload, buf, count);
+
+ ret = qcom_smd_send(rpm->rpm_channel, &pkt, sizeof(pkt));
+ if (ret)
+ goto out;
+
+ left = wait_for_completion_timeout(&rpm->ack, RPM_REQUEST_TIMEOUT);
+ if (!left)
+ ret = -ETIMEDOUT;
+ else
+ ret = rpm->ack_status;
+
+out:
+ mutex_unlock(&rpm->lock);
+ return ret;
+}
+EXPORT_SYMBOL(qcom_rpm_smd_write);
+
+#define RPM_ERR_INVALID_RESOURCE "resource does not exist"
+
+static int qcom_smd_rpm_callback(struct qcom_smd_device *qsdev,
+ const void *data,
+ size_t count)
+{
+ const struct qcom_rpm_header *hdr = data;
+ const struct qcom_rpm_message *msg;
+ const size_t inv_res_len = sizeof(RPM_ERR_INVALID_RESOURCE) - 1;
+ struct qcom_smd_rpm *rpm = dev_get_drvdata(&qsdev->dev);
+ const u8 *buf = data + sizeof(struct qcom_rpm_header);
+ const u8 *end = buf + hdr->length;
+ int status = 0;
+
+ if (hdr->service_type != RPM_SERVICE_TYPE_REQUEST ||
+ hdr->length < sizeof(struct qcom_rpm_message)) {
+ dev_err(&qsdev->dev, "invalid request\n");
+ return 0;
+ }
+
+ while (buf < end) {
+ msg = (struct qcom_rpm_message *)buf;
+ switch (msg->msg_type) {
+ case RPM_MSG_TYPE_MSG_ID:
+ break;
+ case RPM_MSG_TYPE_ERR:
+ if (msg->length == inv_res_len &&
+ !memcmp(msg->message,
+ RPM_ERR_INVALID_RESOURCE,
+ inv_res_len))
+ status = -ENXIO;
+ else
+ status = -EIO;
+ break;
+ }
+
+ buf = PTR_ALIGN(buf + 2 * sizeof(u32) + msg->length, 4);
+ }
+
+ rpm->ack_status = status;
+ complete(&rpm->ack);
+ return 0;
+}
+
+static int qcom_smd_rpm_probe(struct qcom_smd_device *sdev)
+{
+ struct qcom_smd_rpm *rpm;
+
+ rpm = devm_kzalloc(&sdev->dev, sizeof(*rpm), GFP_KERNEL);
+ if (!rpm)
+ return -ENOMEM;
+
+ mutex_init(&rpm->lock);
+ init_completion(&rpm->ack);
+
+ rpm->rpm_channel = sdev->channel;
+
+ dev_set_drvdata(&sdev->dev, rpm);
+
+ return of_platform_populate(sdev->dev.of_node, NULL, NULL, &sdev->dev);
+}
+
+static void qcom_smd_rpm_remove(struct qcom_smd_device *sdev)
+{
+ of_platform_depopulate(&sdev->dev);
+}
+
+static const struct of_device_id qcom_smd_rpm_of_match[] = {
+ { .compatible = "qcom,rpm-msm8974" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, qcom_smd_rpm_of_match);
+
+static struct qcom_smd_driver qcom_smd_rpm_driver = {
+ .probe = qcom_smd_rpm_probe,
+ .remove = qcom_smd_rpm_remove,
+ .callback = qcom_smd_rpm_callback,
+ .driver = {
+ .name = "qcom_smd_rpm",
+ .owner = THIS_MODULE,
+ .of_match_table = qcom_smd_rpm_of_match,
+ },
+};
+
+module_qcom_smd_driver(qcom_smd_rpm_driver);
+
+MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@sonymobile.com>");
+MODULE_DESCRIPTION("Qualcomm SMD backed RPM driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/mfd/qcom-smd-rpm.h b/include/linux/mfd/qcom-smd-rpm.h
new file mode 100644
index 0000000..2a53dca
--- /dev/null
+++ b/include/linux/mfd/qcom-smd-rpm.h
@@ -0,0 +1,35 @@
+#ifndef __QCOM_SMD_RPM_H__
+#define __QCOM_SMD_RPM_H__
+
+struct qcom_smd_rpm;
+
+#define QCOM_SMD_RPM_ACTIVE_STATE 0
+#define QCOM_SMD_RPM_SLEEP_STATE 1
+
+/*
+ * Constants used for addressing resources in the RPM.
+ */
+#define QCOM_SMD_RPM_BOOST 0x61747362
+#define QCOM_SMD_RPM_BUS_CLK 0x316b6c63
+#define QCOM_SMD_RPM_BUS_MASTER 0x73616d62
+#define QCOM_SMD_RPM_BUS_SLAVE 0x766c7362
+#define QCOM_SMD_RPM_CLK_BUF_A 0x616B6C63
+#define QCOM_SMD_RPM_LDOA 0x616f646c
+#define QCOM_SMD_RPM_LDOB 0x626F646C
+#define QCOM_SMD_RPM_MEM_CLK 0x326b6c63
+#define QCOM_SMD_RPM_MISC_CLK 0x306b6c63
+#define QCOM_SMD_RPM_NCPA 0x6170636E
+#define QCOM_SMD_RPM_NCPB 0x6270636E
+#define QCOM_SMD_RPM_OCMEM_PWR 0x706d636f
+#define QCOM_SMD_RPM_QPIC_CLK 0x63697071
+#define QCOM_SMD_RPM_SMPA 0x61706d73
+#define QCOM_SMD_RPM_SMPB 0x62706d73
+#define QCOM_SMD_RPM_SPDM 0x63707362
+#define QCOM_SMD_RPM_VSA 0x00617376
+
+int qcom_rpm_smd_write(struct qcom_smd_rpm *rpm,
+ int state,
+ u32 resource_type, u32 resource_id,
+ void *buf, size_t count);
+
+#endif
--
1.9.3 (Apple Git-50)