diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/hsi/clients/nokia-modem.c | 298 |
1 files changed, 298 insertions, 0 deletions
diff --git a/drivers/hsi/clients/nokia-modem.c b/drivers/hsi/clients/nokia-modem.c new file mode 100644 index 000000000..97ba59e60 --- /dev/null +++ b/drivers/hsi/clients/nokia-modem.c @@ -0,0 +1,298 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * nokia-modem.c + * + * HSI client driver for Nokia N900 modem. + * + * Copyright (C) 2014 Sebastian Reichel <sre@kernel.org> + */ + +#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 <sre@kernel.org>"); +MODULE_DESCRIPTION("HSI driver module for Nokia N900 Modem"); +MODULE_LICENSE("GPL"); |