diff options
author | Philippe Langlais <philippe.langlais@linaro.org> | 2012-03-19 09:24:14 +0100 |
---|---|---|
committer | Philippe Langlais <philippe.langlais@linaro.org> | 2012-03-19 09:24:14 +0100 |
commit | f7733363e6625437f4d42faf58d22dfd247a6c77 (patch) | |
tree | 4c837a761d8e1a6d8489624433edb52944d492fe /drivers/modem/m6718_spi/modem_driver.c | |
parent | 2c69f23b00d63695704fffb24571d7b5bf857403 (diff) | |
parent | dccf714b737a9e6de759045f32ba07d93ada36e5 (diff) |
Merge topic branch 'modem' into integration-linux-ux500-3.3
Diffstat (limited to 'drivers/modem/m6718_spi/modem_driver.c')
-rw-r--r-- | drivers/modem/m6718_spi/modem_driver.c | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/drivers/modem/m6718_spi/modem_driver.c b/drivers/modem/m6718_spi/modem_driver.c new file mode 100644 index 00000000000..8086e97aa7c --- /dev/null +++ b/drivers/modem/m6718_spi/modem_driver.c @@ -0,0 +1,292 @@ +/* + * Copyright (C) ST-Ericsson SA 2011 + * + * Author: Chris Blair <chris.blair@stericsson.com> for ST-Ericsson + * based on modem_shrm_driver.c + * + * License terms: GNU General Public License (GPL) version 2 + * + * SPI driver implementing the M6718 inter-processor communication protocol. + */ +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/spi/spi.h> +#include <linux/modem/modem_client.h> +#include <linux/modem/m6718_spi/modem_driver.h> +#include <linux/modem/m6718_spi/modem_net.h> +#include <linux/modem/m6718_spi/modem_char.h> +#include "modem_protocol.h" + +#ifdef CONFIG_PHONET +static void phonet_rcv_tasklet_func(unsigned long); +static struct tasklet_struct phonet_rcv_tasklet; +#endif + +static struct modem_spi_dev modem_driver_data = { + .dev = NULL, + .ndev = NULL, + .modem = NULL, + .isa_context = NULL, + .netdev_flag_up = 0 +}; + +/** + * modem_m6718_spi_receive() - Receive a frame from L1 physical layer + * @sdev: pointer to spi device structure + * @channel: L2 mux channel id + * @len: frame data length + * @data: pointer to frame data + * + * This function is called from the driver L1 physical transport layer. It + * copies the frame data to the receive queue for the channel on which the data + * was received. + * + * Special handling is given to slave-loopback channels where the data is simply + * sent back to the modem on the same channel. + * + * Special handling is given to the ISI channel when PHONET is enabled - the + * phonet tasklet is scheduled in order to pump the received data through the + * net device interface. + */ +int modem_m6718_spi_receive(struct spi_device *sdev, u8 channel, + u32 len, void *data) +{ + u32 size = 0; + int ret = 0; + int idx; + u8 *psrc; + u32 writeptr; + struct message_queue *q; + struct isa_device_context *isadev; + + dev_dbg(&sdev->dev, "L2 received frame from L1: channel %d len %d\n", + channel, len); + +#ifdef CONFIG_MODEM_M6718_SPI_ENABLE_FEATURE_LOOPBACK + if (channel == MODEM_M6718_SPI_CHN_SLAVE_LOOPBACK0 || + channel == MODEM_M6718_SPI_CHN_SLAVE_LOOPBACK1) { + /* data received on slave loopback channel - loop it back */ + modem_m6718_spi_send(&modem_driver_data, channel, len, data); + return 0; + } +#endif + + /* find the isa device index for this L2 channel */ + idx = modem_get_cdev_index(channel); + if (idx < 0) { + dev_err(&sdev->dev, "failed to get isa device index\n"); + return idx; + } + isadev = &modem_driver_data.isa_context->isadev[idx]; + q = &isadev->dl_queue; + + spin_lock(&q->update_lock); + + /* verify message can be contained in buffer */ + writeptr = q->writeptr; + ret = modem_isa_queue_msg(q, len); + if (ret >= 0) { + /* memcopy RX data */ + if ((writeptr + len) >= q->size) { + psrc = (u8 *)data; + size = q->size - writeptr; + /* copy first part of msg */ + memcpy((q->fifo_base + writeptr), psrc, size); + psrc += size; + /* copy second part of msg at the top of fifo */ + memcpy(q->fifo_base, psrc, (len - size)); + } else { + memcpy((q->fifo_base + writeptr), data, len); + } + } + spin_unlock(&q->update_lock); + + if (ret < 0) { + dev_err(&sdev->dev, "failed to queue frame!"); + return ret; + } + +#ifdef CONFIG_PHONET + if (channel == MODEM_M6718_SPI_CHN_ISI && + modem_driver_data.netdev_flag_up) + tasklet_schedule(&phonet_rcv_tasklet); +#endif + return ret; +} +EXPORT_SYMBOL_GPL(modem_m6718_spi_receive); + +static void phonet_rcv_tasklet_func(unsigned long unused) +{ + ssize_t result; + + dev_dbg(modem_driver_data.dev, "receiving frames for phonet\n"); + /* continue receiving while there are frames in the queue */ + for (;;) { + result = modem_net_receive(modem_driver_data.ndev); + if (result == 0) { + dev_dbg(modem_driver_data.dev, + "queue is empty, finished receiving\n"); + break; + } + if (result < 0) { + dev_err(modem_driver_data.dev, + "failed to receive frame from queue!\n"); + break; + } + } +} + +static int spi_probe(struct spi_device *sdev) +{ + int result = 0; + + spi_set_drvdata(sdev, &modem_driver_data); + + if (modem_protocol_probe(sdev) != 0) { + dev_err(&sdev->dev, + "failed to initialise link protocol\n"); + result = -ENODEV; + goto rollback; + } + + /* + * Since we can have multiple spi links for the same modem, only + * initialise the modem data and char/net interfaces once. + */ + if (modem_driver_data.dev == NULL) { + modem_driver_data.dev = &sdev->dev; + modem_driver_data.modem = + modem_get(modem_driver_data.dev, "m6718"); + if (modem_driver_data.modem == NULL) { + dev_err(&sdev->dev, + "failed to retrieve modem description\n"); + result = -ENODEV; + goto rollback_protocol_init; + } + + result = modem_isa_init(&modem_driver_data); + if (result < 0) { + dev_err(&sdev->dev, + "failed to initialise char interface\n"); + goto rollback_modem_get; + } + + result = modem_net_init(&modem_driver_data); + if (result < 0) { + dev_err(&sdev->dev, + "failed to initialse net interface\n"); + goto rollback_isa_init; + } + +#ifdef CONFIG_PHONET + tasklet_init(&phonet_rcv_tasklet, phonet_rcv_tasklet_func, 0); +#endif + } + return result; + +rollback_isa_init: + modem_isa_exit(&modem_driver_data); +rollback_modem_get: + modem_put(modem_driver_data.modem); +rollback_protocol_init: + modem_protocol_exit(); +rollback: + return result; +} + +static int __exit spi_remove(struct spi_device *sdev) +{ + modem_protocol_exit(); + modem_net_exit(&modem_driver_data); + modem_isa_exit(&modem_driver_data); + return 0; +} + +#ifdef CONFIG_PM +/** + * spi_suspend() - This routine puts the IPC driver in to suspend state. + * @sdev: pointer to spi device structure. + * @mesg: pm operation + * + * This routine checks the current ongoing communication with modem + * and prevents suspend if modem communication is on-going. + */ +static int spi_suspend(struct spi_device *sdev, pm_message_t mesg) +{ + bool busy; + int ret = -EBUSY; + + dev_dbg(&sdev->dev, "suspend called\n"); + busy = modem_protocol_is_busy(sdev); + if (busy) { + dev_warn(&sdev->dev, "suspend failed (protocol busy)\n"); + return -EBUSY; + } + ret = modem_protocol_suspend(sdev); + if (ret) { + dev_warn(&sdev->dev, "suspend failed, (protocol suspend))\n"); + return ret; + } + ret = modem_net_suspend(modem_driver_data.ndev); + if (ret) { + dev_warn(&sdev->dev, "suspend failed, (netdev suspend)\n"); + return ret; + } + return 0; +} + +/** + * spi_resume() - This routine resumes the IPC driver from suspend state. + * @sdev: pointer to spi device structure + */ +static int spi_resume(struct spi_device *sdev) +{ + int ret; + + dev_dbg(&sdev->dev, "resume called\n"); + ret = modem_protocol_resume(sdev); + if (ret) { + dev_warn(&sdev->dev, "resume failed, (protocol resume))\n"); + return ret; + } + ret = modem_net_resume(modem_driver_data.ndev); + if (ret) { + dev_warn(&sdev->dev, "resume failed, (netdev resume))\n"); + return ret; + } + return 0; +} +#endif /* CONFIG_PM */ + +static struct spi_driver spi_driver = { + .driver = { + .name = "spimodem", + .bus = &spi_bus_type, + .owner = THIS_MODULE + }, + .probe = spi_probe, + .remove = __exit_p(spi_remove), +#ifdef CONFIG_PM + .suspend = spi_suspend, + .resume = spi_resume, +#endif +}; + +static int __init m6718_spi_driver_init(void) +{ + pr_info("M6718 modem driver initialising\n"); + modem_protocol_init(); + return spi_register_driver(&spi_driver); +} +module_init(m6718_spi_driver_init); + +static void __exit m6718_spi_driver_exit(void) +{ + pr_debug("M6718 modem SPI IPC driver exit\n"); + spi_unregister_driver(&spi_driver); +} +module_exit(m6718_spi_driver_exit); + +MODULE_AUTHOR("Chris Blair <chris.blair@stericsson.com>"); +MODULE_DESCRIPTION("M6718 modem IPC SPI driver"); +MODULE_LICENSE("GPL v2"); |