/* * 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 #include #include #include #include #include #include #include #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 device *dev; 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 { __le32 service_type; __le32 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 { __le32 msg_id; __le32 flags; __le32 type; __le32 id; __le32 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 { __le32 msg_type; __le32 length; union { __le32 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[]; } *pkt; size_t size = sizeof(*pkt) + count; /* SMD packets to the RPM may not exceed 256 bytes */ if (WARN_ON(size >= 256)) return -EINVAL; pkt = kmalloc(size, GFP_KERNEL); if (!pkt) return -ENOMEM; mutex_lock(&rpm->lock); pkt->hdr.service_type = cpu_to_le32(RPM_SERVICE_TYPE_REQUEST); pkt->hdr.length = cpu_to_le32(sizeof(struct qcom_rpm_request) + count); pkt->req.msg_id = cpu_to_le32(msg_id++); pkt->req.flags = cpu_to_le32(state); pkt->req.type = cpu_to_le32(type); pkt->req.id = cpu_to_le32(id); pkt->req.data_len = cpu_to_le32(count); memcpy(pkt->payload, buf, count); ret = qcom_smd_send(rpm->rpm_channel, pkt, size); if (ret) goto out; left = wait_for_completion_timeout(&rpm->ack, RPM_REQUEST_TIMEOUT); if (!left) ret = -ETIMEDOUT; else ret = rpm->ack_status; out: kfree(pkt); mutex_unlock(&rpm->lock); return ret; } EXPORT_SYMBOL(qcom_rpm_smd_write); static int qcom_smd_rpm_callback(struct qcom_smd_channel *channel, const void *data, size_t count) { const struct qcom_rpm_header *hdr = data; size_t hdr_length = le32_to_cpu(hdr->length); const struct qcom_rpm_message *msg; struct qcom_smd_rpm *rpm = qcom_smd_get_drvdata(channel); const u8 *buf = data + sizeof(struct qcom_rpm_header); const u8 *end = buf + hdr_length; char msgbuf[32]; int status = 0; u32 len, msg_length; if (le32_to_cpu(hdr->service_type) != RPM_SERVICE_TYPE_REQUEST || hdr_length < sizeof(struct qcom_rpm_message)) { dev_err(rpm->dev, "invalid request\n"); return 0; } while (buf < end) { msg = (struct qcom_rpm_message *)buf; msg_length = le32_to_cpu(msg->length); switch (le32_to_cpu(msg->msg_type)) { case RPM_MSG_TYPE_MSG_ID: break; case RPM_MSG_TYPE_ERR: len = min_t(u32, ALIGN(msg_length, 4), sizeof(msgbuf)); memcpy_fromio(msgbuf, msg->message, len); msgbuf[len - 1] = 0; if (!strcmp(msgbuf, "resource does not exist")) status = -ENXIO; else status = -EINVAL; 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->dev = &sdev->dev; rpm->rpm_channel = sdev->channel; qcom_smd_set_drvdata(sdev->channel, rpm); 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-apq8084" }, { .compatible = "qcom,rpm-msm8916" }, { .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, }, }; static int __init qcom_smd_rpm_init(void) { return qcom_smd_driver_register(&qcom_smd_rpm_driver); } arch_initcall(qcom_smd_rpm_init); static void __exit qcom_smd_rpm_exit(void) { qcom_smd_driver_unregister(&qcom_smd_rpm_driver); } module_exit(qcom_smd_rpm_exit); MODULE_AUTHOR("Bjorn Andersson "); MODULE_DESCRIPTION("Qualcomm SMD backed RPM driver"); MODULE_LICENSE("GPL v2");