// SPDX-License-Identifier: GPL-2.0-only
/*
* nokia-modem.c
*
* HSI client driver for Nokia N900 modem.
*
* Copyright (C) 2014 Sebastian Reichel <[email protected]>
*/
#include <linux/gpio/consumer.h>
#include <linux/hsi/hsi.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/hsi/ssi_protocol.h>
static unsigned int pm = 1;
module_param(pm, int, 0400);
MODULE_PARM_DESC(pm,
"Enable power management (0=disabled, 1=userland based [default])");
struct nokia_modem_gpio {
struct gpio_desc *gpio;
const char *name;
};
struct nokia_modem_device {
struct tasklet_struct nokia_modem_rst_ind_tasklet;
int nokia_modem_rst_ind_irq;
struct device *device;
struct nokia_modem_gpio *gpios;
int gpio_amount;
struct hsi_client *ssi_protocol;
struct hsi_client *cmt_speech;
};
static void do_nokia_modem_rst_ind_tasklet(unsigned long data)
{
struct nokia_modem_device *modem = (struct nokia_modem_device *)data;
if (!modem)
return;
dev_info(modem->device, "CMT rst line change detected\n");
if (modem->ssi_protocol)
ssip_reset_event(modem->ssi_protocol);
}
static irqreturn_t nokia_modem_rst_ind_isr(int irq, void *data)
{
struct nokia_modem_device *modem = (struct nokia_modem_device *)data;
tasklet_schedule(&modem->nokia_modem_rst_ind_tasklet);
return IRQ_HANDLED;
}
static void nokia_modem_gpio_unexport(struct device *dev)
{
struct nokia_modem_device *modem = dev_get_drvdata(dev);
int i;
for (i = 0; i < modem->gpio_amount; i++) {
sysfs_remove_link(&dev->kobj, modem->gpios[i].name);
gpiod_unexport(modem->gpios[i].gpio);
}
}
static int nokia_modem_gpio_probe(struct device *dev)
{
struct device_node *np = dev->of_node;
struct nokia_modem_device *modem = dev_get_drvdata(dev);
int gpio_count, gpio_name_count, i, err;
gpio_count = gpiod_count(dev, NULL);
if (gpio_count < 0) {
dev_err(dev, "missing gpios: %d\n", gpio_count);
return gpio_count;
}
gpio_name_count = of_property_count_strings(np, "gpio-names");
if (gpio_count != gpio_name_count) {
dev_err(dev, "number of gpios does not equal number of gpio names\n");
return -EINVAL;
}
modem->gpios = devm_kcalloc(dev, gpio_count, sizeof(*modem->gpios),
GFP_KERNEL);
if (!modem->gpios)
return -ENOMEM;
modem->gpio_amount = gpio_count;
for (i = 0; i < gpio_count; i++) {
modem->gpios[i].gpio = devm_gpiod_get_index(dev, NULL, i,
GPIOD_OUT_LOW);
if (IS_ERR(modem->gpios[i].gpio)) {
dev_err(dev, "Could not get gpio %d\n", i);
return PTR_ERR(modem->gpios[i].gpio);
}
err = of_property_read_string_index(np, "gpio-names", i,
&(modem->gpios[i].name));
if (err) {
dev_err(dev, "Could not get gpio name %d\n", i);
return err;
}
err = gpiod_export(modem->gpios[i].gpio, 0);
if (err)
return err;
err = gpiod_export_link(dev, modem->gpios[i].name,
modem->gpios[i].gpio);
if (err)
return err;
}
return 0;
}
static int nokia_modem_probe(struct device *dev)
{
struct device_node *np;
struct nokia_modem_device *modem;
struct hsi_client *cl = to_hsi_client(dev);
struct hsi_port *port = hsi_get_port(cl);
int irq, pflags, err;
struct hsi_board_info ssip;
struct hsi_board_info cmtspeech;
np = dev->of_node;
if (!np) {
dev_err(dev, "device tree node not found\n");
return -ENXIO;
}
modem = devm_kzalloc(dev, sizeof(*modem), GFP_KERNEL);
if (!modem)
return -ENOMEM;
dev_set_drvdata(dev, modem);
modem->device = dev;
irq = irq_of_parse_and_map(np, 0);
if (!irq) {
dev_err(dev, "Invalid rst_ind interrupt (%d)\n", irq);
return -EINVAL;
}
modem->nokia_modem_rst_ind_irq = irq;
pflags = irq_get_trigger_type(irq);
tasklet_init(&modem->nokia_modem_rst_ind_tasklet,
do_nokia_modem_rst_ind_tasklet, (unsigned long)modem);
err = devm_request_irq(dev, irq, nokia_modem_rst_ind_isr,
pflags, "modem_rst_ind", modem);
if (err < 0) {
dev_err(dev, "Request rst_ind irq(%d) failed (flags %d)\n",
irq, pflags);
return err;
}
enable_irq_wake(irq);
if (pm) {
err = nokia_modem_gpio_probe(dev);
if (err < 0) {
dev_err(dev, "Could not probe GPIOs\n");
goto error1;
}
}
ssip.name = "ssi-protocol";
ssip.tx_cfg = cl->tx_cfg;
ssip.rx_cfg = cl->rx_cfg;
ssip.platform_data = NULL;
ssip.archdata = NULL;
modem->ssi_protocol = hsi_new_client(port, &ssip);
if (!modem->ssi_protocol) {
dev_err(dev, "Could not register ssi-protocol device\n");
err = -ENOMEM;
goto error2;
}
err = device_attach(&modem->ssi_protocol->device);
if (err == 0) {
dev_dbg(dev, "Missing ssi-protocol driver\n");
err = -EPROBE_DEFER;
goto error3;
} else if (err < 0) {
dev_err(dev, "Could not load ssi-protocol driver (%d)\n", err);
goto error3;
}
cmtspeech.name = "cmt-speech";
cmtspeech.tx_cfg = cl->tx_cfg;
cmtspeech.rx_cfg = cl->rx_cfg;
cmtspeech.platform_data = NULL;
cmtspeech.archdata = NULL;
modem->cmt_speech = hsi_new_client(port, &cmtspeech);
if (!modem->cmt_speech) {
dev_err(dev, "Could not register cmt-speech device\n");
err = -ENOMEM;
goto error3;
}
err = device_attach(&modem->cmt_speech->device);
if (err == 0) {
dev_dbg(dev, "Missing cmt-speech driver\n");
err = -EPROBE_DEFER;
goto error4;
} else if (err < 0) {
dev_err(dev, "Could not load cmt-speech driver (%d)\n", err);
goto error4;
}
dev_info(dev, "Registered Nokia HSI modem\n");
return 0;
error4:
hsi_remove_client(&modem->cmt_speech->device, NULL);
error3:
hsi_remove_client(&modem->ssi_protocol->device, NULL);
error2:
nokia_modem_gpio_unexport(dev);
error1:
disable_irq_wake(modem->nokia_modem_rst_ind_irq);
tasklet_kill(&modem->nokia_modem_rst_ind_tasklet);
return err;
}
static int nokia_modem_remove(struct device *dev)
{
struct nokia_modem_device *modem = dev_get_drvdata(dev);
if (!modem)
return 0;
if (modem->cmt_speech) {
hsi_remove_client(&modem->cmt_speech->device, NULL);
modem->cmt_speech = NULL;
}
if (modem->ssi_protocol) {
hsi_remove_client(&modem->ssi_protocol->device, NULL);
modem->ssi_protocol = NULL;
}
nokia_modem_gpio_unexport(dev);
dev_set_drvdata(dev, NULL);
disable_irq_wake(modem->nokia_modem_rst_ind_irq);
tasklet_kill(&modem->nokia_modem_rst_ind_tasklet);
return 0;
}
#ifdef CONFIG_OF
static const struct of_device_id nokia_modem_of_match[] = {
{ .compatible = "nokia,n900-modem", },
{ .compatible = "nokia,n950-modem", },
{ .compatible = "nokia,n9-modem", },
{},
};
MODULE_DEVICE_TABLE(of, nokia_modem_of_match);
#endif
static struct hsi_client_driver nokia_modem_driver = {
.driver = {
.name = "nokia-modem",
.owner = THIS_MODULE,
.probe = nokia_modem_probe,
.remove = nokia_modem_remove,
.of_match_table = of_match_ptr(nokia_modem_of_match),
},
};
static int __init nokia_modem_init(void)
{
return hsi_register_client_driver(&nokia_modem_driver);
}
module_init(nokia_modem_init);
static void __exit nokia_modem_exit(void)
{
hsi_unregister_client_driver(&nokia_modem_driver);
}
module_exit(nokia_modem_exit);
MODULE_ALIAS("hsi:nokia-modem");
MODULE_AUTHOR("Sebastian Reichel <[email protected]>");
MODULE_DESCRIPTION("HSI driver module for Nokia N900 Modem");
MODULE_LICENSE("GPL");
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