Commit a2aa2473 authored by Sebastian Reichel's avatar Sebastian Reichel

HSI: Add common DT binding for HSI client devices

Implement and document generic DT bindings for HSI clients.
Signed-off-by: default avatarSebastian Reichel <sre@kernel.org>
Reviewed-by: default avatarPavel Machek <pavel@ucw.cz>
Tested-By: default avatarIvaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
parent 84914510
Each HSI port is supposed to have one child node, which
symbols the remote device connected to the HSI port. The
following properties are standardized for HSI clients:
Required HSI configuration properties:
- hsi-channel-ids: A list of channel ids
- hsi-rx-mode: Receiver Bit transmission mode ("stream" or "frame")
- hsi-tx-mode: Transmitter Bit transmission mode ("stream" or "frame")
- hsi-mode: May be used instead hsi-rx-mode and hsi-tx-mode if
the transmission mode is the same for receiver and
transmitter
- hsi-speed-kbps: Max bit transmission speed in kbit/s
- hsi-flow: RX flow type ("synchronized" or "pipeline")
- hsi-arb-mode: Arbitration mode for TX frame ("round-robin", "priority")
Optional HSI configuration properties:
- hsi-channel-names: A list with one name per channel specified in the
hsi-channel-ids property
Device Tree node example for an HSI client:
hsi-controller {
hsi-port {
modem: hsi-client {
compatible = "nokia,n900-modem";
hsi-channel-ids = <0>, <1>, <2>, <3>;
hsi-channel-names = "mcsaab-control",
"speech-control",
"speech-data",
"mcsaab-data";
hsi-speed-kbps = <55000>;
hsi-mode = "frame";
hsi-flow = "synchronized";
hsi-arb-mode = "round-robin";
/* more client specific properties */
};
};
};
......@@ -26,6 +26,8 @@
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/notifier.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include "hsi_core.h"
static ssize_t modalias_show(struct device *dev,
......@@ -50,7 +52,13 @@ static int hsi_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
static int hsi_bus_match(struct device *dev, struct device_driver *driver)
{
return strcmp(dev_name(dev), driver->name) == 0;
if (of_driver_match_device(dev, driver))
return true;
if (strcmp(dev_name(dev), driver->name) == 0)
return true;
return false;
}
static struct bus_type hsi_bus_type = {
......@@ -123,6 +131,202 @@ static void hsi_scan_board_info(struct hsi_controller *hsi)
}
}
#ifdef CONFIG_OF
static struct hsi_board_info hsi_char_dev_info = {
.name = "hsi_char",
};
static int hsi_of_property_parse_mode(struct device_node *client, char *name,
unsigned int *result)
{
const char *mode;
int err;
err = of_property_read_string(client, name, &mode);
if (err < 0)
return err;
if (strcmp(mode, "stream") == 0)
*result = HSI_MODE_STREAM;
else if (strcmp(mode, "frame") == 0)
*result = HSI_MODE_FRAME;
else
return -EINVAL;
return 0;
}
static int hsi_of_property_parse_flow(struct device_node *client, char *name,
unsigned int *result)
{
const char *flow;
int err;
err = of_property_read_string(client, name, &flow);
if (err < 0)
return err;
if (strcmp(flow, "synchronized") == 0)
*result = HSI_FLOW_SYNC;
else if (strcmp(flow, "pipeline") == 0)
*result = HSI_FLOW_PIPE;
else
return -EINVAL;
return 0;
}
static int hsi_of_property_parse_arb_mode(struct device_node *client,
char *name, unsigned int *result)
{
const char *arb_mode;
int err;
err = of_property_read_string(client, name, &arb_mode);
if (err < 0)
return err;
if (strcmp(arb_mode, "round-robin") == 0)
*result = HSI_ARB_RR;
else if (strcmp(arb_mode, "priority") == 0)
*result = HSI_ARB_PRIO;
else
return -EINVAL;
return 0;
}
static void hsi_add_client_from_dt(struct hsi_port *port,
struct device_node *client)
{
struct hsi_client *cl;
struct hsi_channel channel;
struct property *prop;
char name[32];
int length, cells, err, i, max_chan, mode;
cl = kzalloc(sizeof(*cl), GFP_KERNEL);
if (!cl)
return;
err = of_modalias_node(client, name, sizeof(name));
if (err)
goto err;
dev_set_name(&cl->device, "%s", name);
err = hsi_of_property_parse_mode(client, "hsi-mode", &mode);
if (err) {
err = hsi_of_property_parse_mode(client, "hsi-rx-mode",
&cl->rx_cfg.mode);
if (err)
goto err;
err = hsi_of_property_parse_mode(client, "hsi-tx-mode",
&cl->tx_cfg.mode);
if (err)
goto err;
} else {
cl->rx_cfg.mode = mode;
cl->tx_cfg.mode = mode;
}
err = of_property_read_u32(client, "hsi-speed-kbps",
&cl->tx_cfg.speed);
if (err)
goto err;
cl->rx_cfg.speed = cl->tx_cfg.speed;
err = hsi_of_property_parse_flow(client, "hsi-flow",
&cl->rx_cfg.flow);
if (err)
goto err;
err = hsi_of_property_parse_arb_mode(client, "hsi-arb-mode",
&cl->rx_cfg.arb_mode);
if (err)
goto err;
prop = of_find_property(client, "hsi-channel-ids", &length);
if (!prop) {
err = -EINVAL;
goto err;
}
cells = length / sizeof(u32);
cl->rx_cfg.num_channels = cells;
cl->tx_cfg.num_channels = cells;
cl->rx_cfg.channels = kzalloc(cells * sizeof(channel), GFP_KERNEL);
if (!cl->rx_cfg.channels) {
err = -ENOMEM;
goto err;
}
cl->tx_cfg.channels = kzalloc(cells * sizeof(channel), GFP_KERNEL);
if (!cl->tx_cfg.channels) {
err = -ENOMEM;
goto err2;
}
max_chan = 0;
for (i = 0; i < cells; i++) {
err = of_property_read_u32_index(client, "hsi-channel-ids", i,
&channel.id);
if (err)
goto err3;
err = of_property_read_string_index(client, "hsi-channel-names",
i, &channel.name);
if (err)
channel.name = NULL;
if (channel.id > max_chan)
max_chan = channel.id;
cl->rx_cfg.channels[i] = channel;
cl->tx_cfg.channels[i] = channel;
}
cl->rx_cfg.num_hw_channels = max_chan + 1;
cl->tx_cfg.num_hw_channels = max_chan + 1;
cl->device.bus = &hsi_bus_type;
cl->device.parent = &port->device;
cl->device.release = hsi_client_release;
cl->device.of_node = client;
if (device_register(&cl->device) < 0) {
pr_err("hsi: failed to register client: %s\n", name);
put_device(&cl->device);
goto err3;
}
return;
err3:
kfree(cl->tx_cfg.channels);
err2:
kfree(cl->rx_cfg.channels);
err:
kfree(cl);
pr_err("hsi client: missing or incorrect of property: err=%d\n", err);
}
void hsi_add_clients_from_dt(struct hsi_port *port, struct device_node *clients)
{
struct device_node *child;
/* register hsi-char device */
hsi_new_client(port, &hsi_char_dev_info);
for_each_available_child_of_node(clients, child)
hsi_add_client_from_dt(port, child);
}
EXPORT_SYMBOL_GPL(hsi_add_clients_from_dt);
#endif
int hsi_remove_client(struct device *dev, void *data __maybe_unused)
{
device_unregister(dev);
......@@ -505,7 +709,7 @@ int hsi_unregister_port_event(struct hsi_client *cl)
EXPORT_SYMBOL_GPL(hsi_unregister_port_event);
/**
* hsi_event -Notifies clients about port events
* hsi_event - Notifies clients about port events
* @port: Port where the event occurred
* @event: The event type
*
......
......@@ -301,6 +301,17 @@ struct hsi_client *hsi_new_client(struct hsi_port *port,
int hsi_remove_client(struct device *dev, void *data);
void hsi_port_unregister_clients(struct hsi_port *port);
#ifdef CONFIG_OF
void hsi_add_clients_from_dt(struct hsi_port *port,
struct device_node *clients);
#else
static inline void hsi_add_clients_from_dt(struct hsi_port *port,
struct device_node *clients)
{
return;
}
#endif
static inline void hsi_controller_set_drvdata(struct hsi_controller *hsi,
void *data)
{
......
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