/*
* System Control and Power Interface (SCPI) Message Protocol driver
*
* SCPI Message Protocol is used between the System Control Processor(SCP)
* and the Application Processors(AP). The Message Handling Unit(MHU)
* provides a mechanism for inter-processor communication between SCP's
* Cortex M3 and AP.
*
* SCP offers control and management of the core/cluster power states,
* various power domain DVFS including the core/cluster, certain system
* clocks configuration, thermal sensors and many others.
*
* Copyright (C) 2015 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.
*
* You should have received a copy of the GNU General Public License along
* with this program. If not, see .
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#define CMD_ID_SHIFT 0
#define CMD_ID_MASK 0x7f
#define CMD_TOKEN_ID_SHIFT 8
#define CMD_TOKEN_ID_MASK 0xff
#define CMD_DATA_SIZE_SHIFT 16
#define CMD_DATA_SIZE_MASK 0x1ff
#define PACK_SCPI_CMD(cmd_id, tx_sz) \
((((cmd_id) & CMD_ID_MASK) << CMD_ID_SHIFT) | \
(((tx_sz) & CMD_DATA_SIZE_MASK) << CMD_DATA_SIZE_SHIFT))
#define ADD_SCPI_TOKEN(cmd, token) \
((cmd) |= (((token) & CMD_TOKEN_ID_MASK) << CMD_TOKEN_ID_SHIFT))
#define CMD_SIZE(cmd) (((cmd) >> CMD_DATA_SIZE_SHIFT) & CMD_DATA_SIZE_MASK)
#define CMD_UNIQ_MASK (CMD_TOKEN_ID_MASK << CMD_TOKEN_ID_SHIFT | CMD_ID_MASK)
#define CMD_XTRACT_UNIQ(cmd) ((cmd) & CMD_UNIQ_MASK)
#define SCPI_SLOT 0
#define MAX_DVFS_DOMAINS 8
#define MAX_DVFS_OPPS 8
#define DVFS_LATENCY(hdr) (le32_to_cpu(hdr) >> 16)
#define DVFS_OPP_COUNT(hdr) ((le32_to_cpu(hdr) >> 8) & 0xff)
#define PROTOCOL_REV_MINOR_BITS 16
#define PROTOCOL_REV_MINOR_MASK ((1U << PROTOCOL_REV_MINOR_BITS) - 1)
#define PROTOCOL_REV_MAJOR(x) ((x) >> PROTOCOL_REV_MINOR_BITS)
#define PROTOCOL_REV_MINOR(x) ((x) & PROTOCOL_REV_MINOR_MASK)
#define FW_REV_MAJOR_BITS 24
#define FW_REV_MINOR_BITS 16
#define FW_REV_PATCH_MASK ((1U << FW_REV_MINOR_BITS) - 1)
#define FW_REV_MINOR_MASK ((1U << FW_REV_MAJOR_BITS) - 1)
#define FW_REV_MAJOR(x) ((x) >> FW_REV_MAJOR_BITS)
#define FW_REV_MINOR(x) (((x) & FW_REV_MINOR_MASK) >> FW_REV_MINOR_BITS)
#define FW_REV_PATCH(x) ((x) & FW_REV_PATCH_MASK)
#define MAX_RX_TIMEOUT (msecs_to_jiffies(30))
enum scpi_error_codes {
SCPI_SUCCESS = 0, /* Success */
SCPI_ERR_PARAM = 1, /* Invalid parameter(s) */
SCPI_ERR_ALIGN = 2, /* Invalid alignment */
SCPI_ERR_SIZE = 3, /* Invalid size */
SCPI_ERR_HANDLER = 4, /* Invalid handler/callback */
SCPI_ERR_ACCESS = 5, /* Invalid access/permission denied */
SCPI_ERR_RANGE = 6, /* Value out of range */
SCPI_ERR_TIMEOUT = 7, /* Timeout has occurred */
SCPI_ERR_NOMEM = 8, /* Invalid memory area or pointer */
SCPI_ERR_PWRSTATE = 9, /* Invalid power state */
SCPI_ERR_SUPPORT = 10, /* Not supported or disabled */
SCPI_ERR_DEVICE = 11, /* Device error */
SCPI_ERR_BUSY = 12, /* Device busy */
SCPI_ERR_MAX
};
enum scpi_std_cmd {
SCPI_CMD_INVALID = 0x00,
SCPI_CMD_SCPI_READY = 0x01,
SCPI_CMD_SCPI_CAPABILITIES = 0x02,
SCPI_CMD_SET_CSS_PWR_STATE = 0x03,
SCPI_CMD_GET_CSS_PWR_STATE = 0x04,
SCPI_CMD_SET_SYS_PWR_STATE = 0x05,
SCPI_CMD_SET_CPU_TIMER = 0x06,
SCPI_CMD_CANCEL_CPU_TIMER = 0x07,
SCPI_CMD_DVFS_CAPABILITIES = 0x08,
SCPI_CMD_GET_DVFS_INFO = 0x09,
SCPI_CMD_SET_DVFS = 0x0a,
SCPI_CMD_GET_DVFS = 0x0b,
SCPI_CMD_GET_DVFS_STAT = 0x0c,
SCPI_CMD_CLOCK_CAPABILITIES = 0x0d,
SCPI_CMD_GET_CLOCK_INFO = 0x0e,
SCPI_CMD_SET_CLOCK_VALUE = 0x0f,
SCPI_CMD_GET_CLOCK_VALUE = 0x10,
SCPI_CMD_PSU_CAPABILITIES = 0x11,
SCPI_CMD_GET_PSU_INFO = 0x12,
SCPI_CMD_SET_PSU = 0x13,
SCPI_CMD_GET_PSU = 0x14,
SCPI_CMD_SENSOR_CAPABILITIES = 0x15,
SCPI_CMD_SENSOR_INFO = 0x16,
SCPI_CMD_SENSOR_VALUE = 0x17,
SCPI_CMD_SENSOR_CFG_PERIODIC = 0x18,
SCPI_CMD_SENSOR_CFG_BOUNDS = 0x19,
SCPI_CMD_SENSOR_ASYNC_VALUE = 0x1a,
SCPI_CMD_SET_DEVICE_PWR_STATE = 0x1b,
SCPI_CMD_GET_DEVICE_PWR_STATE = 0x1c,
SCPI_CMD_COUNT
};
struct scpi_xfer {
u32 slot; /* has to be first element */
u32 cmd;
u32 status;
const void *tx_buf;
void *rx_buf;
unsigned int tx_len;
unsigned int rx_len;
struct list_head node;
struct completion done;
};
struct scpi_chan {
struct mbox_client cl;
struct mbox_chan *chan;
void __iomem *tx_payload;
void __iomem *rx_payload;
struct list_head rx_pending;
struct list_head xfers_list;
struct scpi_xfer *xfers;
spinlock_t rx_lock; /* locking for the rx pending list */
struct mutex xfers_lock;
u8 token;
};
struct scpi_drvinfo {
u32 protocol_version;
u32 firmware_version;
int num_chans;
atomic_t next_chan;
struct scpi_ops *scpi_ops;
struct scpi_chan *channels;
struct scpi_dvfs_info *dvfs[MAX_DVFS_DOMAINS];
};
/*
* The SCP firmware only executes in little-endian mode, so any buffers
* shared through SCPI should have their contents converted to little-endian
*/
struct scpi_shared_mem {
__le32 command;
__le32 status;
u8 payload[0];
} __packed;
struct scp_capabilities {
__le32 protocol_version;
__le32 event_version;
__le32 platform_version;
__le32 commands[4];
} __packed;
struct clk_get_info {
__le16 id;
__le16 flags;
__le32 min_rate;
__le32 max_rate;
u8 name[20];
} __packed;
struct clk_get_value {
__le32 rate;
} __packed;
struct clk_set_value {
__le16 id;
__le16 reserved;
__le32 rate;
} __packed;
struct dvfs_info {
__le32 header;
struct {
__le32 freq;
__le32 m_volt;
} opps[MAX_DVFS_OPPS];
} __packed;
struct dvfs_set {
u8 domain;
u8 index;
} __packed;
struct sensor_capabilities {
__le16 sensors;
} __packed;
struct _scpi_sensor_info {
__le16 sensor_id;
u8 class;
u8 trigger_type;
char name[20];
};
struct sensor_value {
__le32 lo_val;
__le32 hi_val;
} __packed;
static struct scpi_drvinfo *scpi_info;
static int scpi_linux_errmap[SCPI_ERR_MAX] = {
/* better than switch case as long as return value is continuous */
0, /* SCPI_SUCCESS */
-EINVAL, /* SCPI_ERR_PARAM */
-ENOEXEC, /* SCPI_ERR_ALIGN */
-EMSGSIZE, /* SCPI_ERR_SIZE */
-EINVAL, /* SCPI_ERR_HANDLER */
-EACCES, /* SCPI_ERR_ACCESS */
-ERANGE, /* SCPI_ERR_RANGE */
-ETIMEDOUT, /* SCPI_ERR_TIMEOUT */
-ENOMEM, /* SCPI_ERR_NOMEM */
-EINVAL, /* SCPI_ERR_PWRSTATE */
-EOPNOTSUPP, /* SCPI_ERR_SUPPORT */
-EIO, /* SCPI_ERR_DEVICE */
-EBUSY, /* SCPI_ERR_BUSY */
};
static inline int scpi_to_linux_errno(int errno)
{
if (errno >= SCPI_SUCCESS && errno < SCPI_ERR_MAX)
return scpi_linux_errmap[errno];
return -EIO;
}
static void scpi_process_cmd(struct scpi_chan *ch, u32 cmd)
{
unsigned long flags;
struct scpi_xfer *t, *match = NULL;
spin_lock_irqsave(&ch->rx_lock, flags);
if (list_empty(&ch->rx_pending)) {
spin_unlock_irqrestore(&ch->rx_lock, flags);
return;
}
list_for_each_entry(t, &ch->rx_pending, node)
if (CMD_XTRACT_UNIQ(t->cmd) == CMD_XTRACT_UNIQ(cmd)) {
list_del(&t->node);
match = t;
break;
}
/* check if wait_for_completion is in progress or timed-out */
if (match && !completion_done(&match->done)) {
struct scpi_shared_mem *mem = ch->rx_payload;
unsigned int len = min(match->rx_len, CMD_SIZE(cmd));
match->status = le32_to_cpu(mem->status);
memcpy_fromio(match->rx_buf, mem->payload, len);
if (match->rx_len > len)
memset(match->rx_buf + len, 0, match->rx_len - len);
complete(&match->done);
}
spin_unlock_irqrestore(&ch->rx_lock, flags);
}
static void scpi_handle_remote_msg(struct mbox_client *c, void *msg)
{
struct scpi_chan *ch = container_of(c, struct scpi_chan, cl);
struct scpi_shared_mem *mem = ch->rx_payload;
u32 cmd = le32_to_cpu(mem->command);
scpi_process_cmd(ch, cmd);
}
static void scpi_tx_prepare(struct mbox_client *c, void *msg)
{
unsigned long flags;
struct scpi_xfer *t = msg;
struct scpi_chan *ch = container_of(c, struct scpi_chan, cl);
struct scpi_shared_mem *mem = (struct scpi_shared_mem *)ch->tx_payload;
if (t->tx_buf)
memcpy_toio(mem->payload, t->tx_buf, t->tx_len);
if (t->rx_buf) {
if (!(++ch->token))
++ch->token;
ADD_SCPI_TOKEN(t->cmd, ch->token);
spin_lock_irqsave(&ch->rx_lock, flags);
list_add_tail(&t->node, &ch->rx_pending);
spin_unlock_irqrestore(&ch->rx_lock, flags);
}
mem->command = cpu_to_le32(t->cmd);
}
static struct scpi_xfer *get_scpi_xfer(struct scpi_chan *ch)
{
struct scpi_xfer *t;
mutex_lock(&ch->xfers_lock);
if (list_empty(&ch->xfers_list)) {
mutex_unlock(&ch->xfers_lock);
return NULL;
}
t = list_first_entry(&ch->xfers_list, struct scpi_xfer, node);
list_del(&t->node);
mutex_unlock(&ch->xfers_lock);
return t;
}
static void put_scpi_xfer(struct scpi_xfer *t, struct scpi_chan *ch)
{
mutex_lock(&ch->xfers_lock);
list_add_tail(&t->node, &ch->xfers_list);
mutex_unlock(&ch->xfers_lock);
}
static int scpi_send_message(u8 cmd, void *tx_buf, unsigned int tx_len,
void *rx_buf, unsigned int rx_len)
{
int ret;
u8 chan;
struct scpi_xfer *msg;
struct scpi_chan *scpi_chan;
chan = atomic_inc_return(&scpi_info->next_chan) % scpi_info->num_chans;
scpi_chan = scpi_info->channels + chan;
msg = get_scpi_xfer(scpi_chan);
if (!msg)
return -ENOMEM;
msg->slot = BIT(SCPI_SLOT);
msg->cmd = PACK_SCPI_CMD(cmd, tx_len);
msg->tx_buf = tx_buf;
msg->tx_len = tx_len;
msg->rx_buf = rx_buf;
msg->rx_len = rx_len;
init_completion(&msg->done);
ret = mbox_send_message(scpi_chan->chan, msg);
if (ret < 0 || !rx_buf)
goto out;
if (!wait_for_completion_timeout(&msg->done, MAX_RX_TIMEOUT))
ret = -ETIMEDOUT;
else
/* first status word */
ret = msg->status;
out:
if (ret < 0 && rx_buf) /* remove entry from the list if timed-out */
scpi_process_cmd(scpi_chan, msg->cmd);
put_scpi_xfer(msg, scpi_chan);
/* SCPI error codes > 0, translate them to Linux scale*/
return ret > 0 ? scpi_to_linux_errno(ret) : ret;
}
static u32 scpi_get_version(void)
{
return scpi_info->protocol_version;
}
static int
scpi_clk_get_range(u16 clk_id, unsigned long *min, unsigned long *max)
{
int ret;
struct clk_get_info clk;
__le16 le_clk_id = cpu_to_le16(clk_id);
ret = scpi_send_message(SCPI_CMD_GET_CLOCK_INFO, &le_clk_id,
sizeof(le_clk_id), &clk, sizeof(clk));
if (!ret) {
*min = le32_to_cpu(clk.min_rate);
*max = le32_to_cpu(clk.max_rate);
}
return ret;
}
static unsigned long scpi_clk_get_val(u16 clk_id)
{
int ret;
struct clk_get_value clk;
__le16 le_clk_id = cpu_to_le16(clk_id);
ret = scpi_send_message(SCPI_CMD_GET_CLOCK_VALUE, &le_clk_id,
sizeof(le_clk_id), &clk, sizeof(clk));
return ret ? ret : le32_to_cpu(clk.rate);
}
static int scpi_clk_set_val(u16 clk_id, unsigned long rate)
{
int stat;
struct clk_set_value clk = {
.id = cpu_to_le16(clk_id),
.rate = cpu_to_le32(rate)
};
return scpi_send_message(SCPI_CMD_SET_CLOCK_VALUE, &clk, sizeof(clk),
&stat, sizeof(stat));
}
static int scpi_dvfs_get_idx(u8 domain)
{
int ret;
u8 dvfs_idx;
ret = scpi_send_message(SCPI_CMD_GET_DVFS, &domain, sizeof(domain),
&dvfs_idx, sizeof(dvfs_idx));
return ret ? ret : dvfs_idx;
}
static int scpi_dvfs_set_idx(u8 domain, u8 index)
{
int stat;
struct dvfs_set dvfs = {domain, index};
return scpi_send_message(SCPI_CMD_SET_DVFS, &dvfs, sizeof(dvfs),
&stat, sizeof(stat));
}
static int opp_cmp_func(const void *opp1, const void *opp2)
{
const struct scpi_opp *t1 = opp1, *t2 = opp2;
return t1->freq - t2->freq;
}
static struct scpi_dvfs_info *scpi_dvfs_get_info(u8 domain)
{
struct scpi_dvfs_info *info;
struct scpi_opp *opp;
struct dvfs_info buf;
int ret, i;
if (domain >= MAX_DVFS_DOMAINS)
return ERR_PTR(-EINVAL);
if (scpi_info->dvfs[domain]) /* data already populated */
return scpi_info->dvfs[domain];
ret = scpi_send_message(SCPI_CMD_GET_DVFS_INFO, &domain, sizeof(domain),
&buf, sizeof(buf));
if (ret)
return ERR_PTR(ret);
info = kmalloc(sizeof(*info), GFP_KERNEL);
if (!info)
return ERR_PTR(-ENOMEM);
info->count = DVFS_OPP_COUNT(buf.header);
info->latency = DVFS_LATENCY(buf.header) * 1000; /* uS to nS */
info->opps = kcalloc(info->count, sizeof(*opp), GFP_KERNEL);
if (!info->opps) {
kfree(info);
return ERR_PTR(-ENOMEM);
}
for (i = 0, opp = info->opps; i < info->count; i++, opp++) {
opp->freq = le32_to_cpu(buf.opps[i].freq);
opp->m_volt = le32_to_cpu(buf.opps[i].m_volt);
}
sort(info->opps, info->count, sizeof(*opp), opp_cmp_func, NULL);
scpi_info->dvfs[domain] = info;
return info;
}
static int scpi_sensor_get_capability(u16 *sensors)
{
struct sensor_capabilities cap_buf;
int ret;
ret = scpi_send_message(SCPI_CMD_SENSOR_CAPABILITIES, NULL, 0, &cap_buf,
sizeof(cap_buf));
if (!ret)
*sensors = le16_to_cpu(cap_buf.sensors);
return ret;
}
static int scpi_sensor_get_info(u16 sensor_id, struct scpi_sensor_info *info)
{
__le16 id = cpu_to_le16(sensor_id);
struct _scpi_sensor_info _info;
int ret;
ret = scpi_send_message(SCPI_CMD_SENSOR_INFO, &id, sizeof(id),
&_info, sizeof(_info));
if (!ret) {
memcpy(info, &_info, sizeof(*info));
info->sensor_id = le16_to_cpu(_info.sensor_id);
}
return ret;
}
static int scpi_sensor_get_value(u16 sensor, u64 *val)
{
__le16 id = cpu_to_le16(sensor);
struct sensor_value buf;
int ret;
ret = scpi_send_message(SCPI_CMD_SENSOR_VALUE, &id, sizeof(id),
&buf, sizeof(buf));
if (!ret)
*val = (u64)le32_to_cpu(buf.hi_val) << 32 |
le32_to_cpu(buf.lo_val);
return ret;
}
static struct scpi_ops scpi_ops = {
.get_version = scpi_get_version,
.clk_get_range = scpi_clk_get_range,
.clk_get_val = scpi_clk_get_val,
.clk_set_val = scpi_clk_set_val,
.dvfs_get_idx = scpi_dvfs_get_idx,
.dvfs_set_idx = scpi_dvfs_set_idx,
.dvfs_get_info = scpi_dvfs_get_info,
.sensor_get_capability = scpi_sensor_get_capability,
.sensor_get_info = scpi_sensor_get_info,
.sensor_get_value = scpi_sensor_get_value,
};
struct scpi_ops *get_scpi_ops(void)
{
return scpi_info ? scpi_info->scpi_ops : NULL;
}
EXPORT_SYMBOL_GPL(get_scpi_ops);
static int scpi_init_versions(struct scpi_drvinfo *info)
{
int ret;
struct scp_capabilities caps;
ret = scpi_send_message(SCPI_CMD_SCPI_CAPABILITIES, NULL, 0,
&caps, sizeof(caps));
if (!ret) {
info->protocol_version = le32_to_cpu(caps.protocol_version);
info->firmware_version = le32_to_cpu(caps.platform_version);
}
return ret;
}
static ssize_t protocol_version_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
return sprintf(buf, "%d.%d\n",
PROTOCOL_REV_MAJOR(scpi_info->protocol_version),
PROTOCOL_REV_MINOR(scpi_info->protocol_version));
}
static DEVICE_ATTR_RO(protocol_version);
static ssize_t firmware_version_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
return sprintf(buf, "%d.%d.%d\n",
FW_REV_MAJOR(scpi_info->firmware_version),
FW_REV_MINOR(scpi_info->firmware_version),
FW_REV_PATCH(scpi_info->firmware_version));
}
static DEVICE_ATTR_RO(firmware_version);
static struct attribute *versions_attrs[] = {
&dev_attr_firmware_version.attr,
&dev_attr_protocol_version.attr,
NULL,
};
ATTRIBUTE_GROUPS(versions);
static void
scpi_free_channels(struct device *dev, struct scpi_chan *pchan, int count)
{
int i;
for (i = 0; i < count && pchan->chan; i++, pchan++) {
mbox_free_channel(pchan->chan);
devm_kfree(dev, pchan->xfers);
devm_iounmap(dev, pchan->rx_payload);
}
}
static int scpi_remove(struct platform_device *pdev)
{
int i;
struct device *dev = &pdev->dev;
struct scpi_drvinfo *info = platform_get_drvdata(pdev);
scpi_info = NULL; /* stop exporting SCPI ops through get_scpi_ops */
of_platform_depopulate(dev);
sysfs_remove_groups(&dev->kobj, versions_groups);
scpi_free_channels(dev, info->channels, info->num_chans);
platform_set_drvdata(pdev, NULL);
for (i = 0; i < MAX_DVFS_DOMAINS && info->dvfs[i]; i++) {
kfree(info->dvfs[i]->opps);
kfree(info->dvfs[i]);
}
devm_kfree(dev, info->channels);
devm_kfree(dev, info);
return 0;
}
#define MAX_SCPI_XFERS 10
static int scpi_alloc_xfer_list(struct device *dev, struct scpi_chan *ch)
{
int i;
struct scpi_xfer *xfers;
xfers = devm_kzalloc(dev, MAX_SCPI_XFERS * sizeof(*xfers), GFP_KERNEL);
if (!xfers)
return -ENOMEM;
ch->xfers = xfers;
for (i = 0; i < MAX_SCPI_XFERS; i++, xfers++)
list_add_tail(&xfers->node, &ch->xfers_list);
return 0;
}
static int scpi_probe(struct platform_device *pdev)
{
int count, idx, ret;
struct resource res;
struct scpi_chan *scpi_chan;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
scpi_info = devm_kzalloc(dev, sizeof(*scpi_info), GFP_KERNEL);
if (!scpi_info)
return -ENOMEM;
count = of_count_phandle_with_args(np, "mboxes", "#mbox-cells");
if (count < 0) {
dev_err(dev, "no mboxes property in '%s'\n", np->full_name);
return -ENODEV;
}
scpi_chan = devm_kcalloc(dev, count, sizeof(*scpi_chan), GFP_KERNEL);
if (!scpi_chan)
return -ENOMEM;
for (idx = 0; idx < count; idx++) {
resource_size_t size;
struct scpi_chan *pchan = scpi_chan + idx;
struct mbox_client *cl = &pchan->cl;
struct device_node *shmem = of_parse_phandle(np, "shmem", idx);
if (of_address_to_resource(shmem, 0, &res)) {
dev_err(dev, "failed to get SCPI payload mem resource\n");
ret = -EINVAL;
goto err;
}
size = resource_size(&res);
pchan->rx_payload = devm_ioremap(dev, res.start, size);
if (!pchan->rx_payload) {
dev_err(dev, "failed to ioremap SCPI payload\n");
ret = -EADDRNOTAVAIL;
goto err;
}
pchan->tx_payload = pchan->rx_payload + (size >> 1);
cl->dev = dev;
cl->rx_callback = scpi_handle_remote_msg;
cl->tx_prepare = scpi_tx_prepare;
cl->tx_block = true;
cl->tx_tout = 20;
cl->knows_txdone = false; /* controller can't ack */
INIT_LIST_HEAD(&pchan->rx_pending);
INIT_LIST_HEAD(&pchan->xfers_list);
spin_lock_init(&pchan->rx_lock);
mutex_init(&pchan->xfers_lock);
ret = scpi_alloc_xfer_list(dev, pchan);
if (!ret) {
pchan->chan = mbox_request_channel(cl, idx);
if (!IS_ERR(pchan->chan))
continue;
ret = PTR_ERR(pchan->chan);
if (ret != -EPROBE_DEFER)
dev_err(dev, "failed to get channel%d err %d\n",
idx, ret);
}
err:
scpi_free_channels(dev, scpi_chan, idx);
scpi_info = NULL;
return ret;
}
scpi_info->channels = scpi_chan;
scpi_info->num_chans = count;
platform_set_drvdata(pdev, scpi_info);
ret = scpi_init_versions(scpi_info);
if (ret) {
dev_err(dev, "incorrect or no SCP firmware found\n");
scpi_remove(pdev);
return ret;
}
_dev_info(dev, "SCP Protocol %d.%d Firmware %d.%d.%d version\n",
PROTOCOL_REV_MAJOR(scpi_info->protocol_version),
PROTOCOL_REV_MINOR(scpi_info->protocol_version),
FW_REV_MAJOR(scpi_info->firmware_version),
FW_REV_MINOR(scpi_info->firmware_version),
FW_REV_PATCH(scpi_info->firmware_version));
scpi_info->scpi_ops = &scpi_ops;
ret = sysfs_create_groups(&dev->kobj, versions_groups);
if (ret)
dev_err(dev, "unable to create sysfs version group\n");
return of_platform_populate(dev->of_node, NULL, NULL, dev);
}
static const struct of_device_id scpi_of_match[] = {
{.compatible = "arm,scpi"},
{},
};
MODULE_DEVICE_TABLE(of, scpi_of_match);
static struct platform_driver scpi_driver = {
.driver = {
.name = "scpi_protocol",
.of_match_table = scpi_of_match,
},
.probe = scpi_probe,
.remove = scpi_remove,
};
module_platform_driver(scpi_driver);
MODULE_AUTHOR("Sudeep Holla ");
MODULE_DESCRIPTION("ARM SCPI mailbox protocol driver");
MODULE_LICENSE("GPL v2");