/* This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 2 as published by the Free Software Foundation. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA This program is distributed in the hope that 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. Copyright (C) 2006-2007 - Motorola Copyright (c) 2008-2010, The Linux Foundation. All rights reserved. Date Author Comment ----------- -------------- -------------------------------- 2006-Apr-28 Motorola The kernel module for running the Bluetooth(R) Sleep-Mode Protocol from the Host side 2006-Sep-08 Motorola Added workqueue for handling sleep work. 2007-Jan-24 Motorola Added mbm_handle_ioi() call to ISR. */ #include /* kernel module definitions */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* event notifications */ #include "hci_uart.h" #define BT_SLEEP_DBG #ifndef BT_SLEEP_DBG #define BT_DBG(fmt, arg...) #endif /* * Defines */ #define VERSION "1.1" #define PROC_DIR "bluetooth/sleep" struct bluesleep_info { unsigned host_wake; unsigned ext_wake; unsigned host_wake_irq; struct uart_port *uport; }; /* work function */ static void bluesleep_sleep_work(struct work_struct *work); /* work queue */ DECLARE_DELAYED_WORK(sleep_workqueue, bluesleep_sleep_work); /* Macros for handling sleep work */ #define bluesleep_rx_busy() schedule_delayed_work(&sleep_workqueue, 0) #define bluesleep_tx_busy() schedule_delayed_work(&sleep_workqueue, 0) #define bluesleep_rx_idle() schedule_delayed_work(&sleep_workqueue, 0) #define bluesleep_tx_idle() schedule_delayed_work(&sleep_workqueue, 0) /* 1 second timeout */ #define TX_TIMER_INTERVAL 1 /* state variable names and bit positions */ #define BT_PROTO 0x01 #define BT_TXDATA 0x02 #define BT_ASLEEP 0x04 /* global pointer to a single hci device. */ static struct hci_dev *bluesleep_hdev; static struct bluesleep_info *bsi; /* module usage */ static atomic_t open_count = ATOMIC_INIT(1); /* * Local function prototypes */ static int bluesleep_hci_event(struct notifier_block *this, unsigned long event, void *data); /* * Global variables */ /** Global state flags */ static unsigned long flags; /** Tasklet to respond to change in hostwake line */ static struct tasklet_struct hostwake_task; /** Transmission timer */ static struct timer_list tx_timer; /** Lock for state transitions */ static spinlock_t rw_lock; /** Notifier block for HCI events */ struct notifier_block hci_event_nblock = { .notifier_call = bluesleep_hci_event, }; struct proc_dir_entry *bluetooth_dir, *sleep_dir; /* * Local functions */ static void hsuart_power(int on) { if (on) { msm_hs_request_clock_on(bsi->uport); msm_hs_set_mctrl(bsi->uport, TIOCM_RTS); } else { msm_hs_set_mctrl(bsi->uport, 0); msm_hs_request_clock_off(bsi->uport); } } /** * @return 1 if the Host can go to sleep, 0 otherwise. */ static inline int bluesleep_can_sleep(void) { /* check if MSM_WAKE_BT_GPIO and BT_WAKE_MSM_GPIO are both deasserted */ return gpio_get_value(bsi->ext_wake) && gpio_get_value(bsi->host_wake) && (bsi->uport != NULL); } void bluesleep_sleep_wakeup(void) { if (test_bit(BT_ASLEEP, &flags)) { BT_DBG("waking up..."); /* Start the timer */ mod_timer(&tx_timer, jiffies + (TX_TIMER_INTERVAL * HZ)); gpio_set_value(bsi->ext_wake, 0); clear_bit(BT_ASLEEP, &flags); /*Activating UART */ hsuart_power(1); } } /** * @brief@ main sleep work handling function which update the flags * and activate and deactivate UART ,check FIFO. */ static void bluesleep_sleep_work(struct work_struct *work) { if (bluesleep_can_sleep()) { /* already asleep, this is an error case */ if (test_bit(BT_ASLEEP, &flags)) { BT_DBG("already asleep"); return; } if (msm_hs_tx_empty(bsi->uport)) { BT_DBG("going to sleep..."); set_bit(BT_ASLEEP, &flags); /*Deactivating UART */ hsuart_power(0); } else { mod_timer(&tx_timer, jiffies + (TX_TIMER_INTERVAL * HZ)); return; } } else { bluesleep_sleep_wakeup(); } } /** * A tasklet function that runs in tasklet context and reads the value * of the HOST_WAKE GPIO pin and further defer the work. * @param data Not used. */ static void bluesleep_hostwake_task(unsigned long data) { BT_DBG("hostwake line change"); spin_lock(&rw_lock); if (gpio_get_value(bsi->host_wake)) bluesleep_rx_busy(); else bluesleep_rx_idle(); spin_unlock(&rw_lock); } /** * Handles proper timer action when outgoing data is delivered to the * HCI line discipline. Sets BT_TXDATA. */ static void bluesleep_outgoing_data(void) { unsigned long irq_flags; spin_lock_irqsave(&rw_lock, irq_flags); /* log data passing by */ set_bit(BT_TXDATA, &flags); /* if the tx side is sleeping... */ if (gpio_get_value(bsi->ext_wake)) { BT_DBG("tx was sleeping"); bluesleep_sleep_wakeup(); } spin_unlock_irqrestore(&rw_lock, irq_flags); } /** * Handles HCI device events. * @param this Not used. * @param event The event that occurred. * @param data The HCI device associated with the event. * @return NOTIFY_DONE. */ static int bluesleep_hci_event(struct notifier_block *this, unsigned long event, void *data) { struct hci_dev *hdev = (struct hci_dev *) data; struct hci_uart *hu; struct uart_state *state; if (!hdev) return NOTIFY_DONE; switch (event) { case HCI_DEV_REG: if (!bluesleep_hdev) { bluesleep_hdev = hdev; hu = (struct hci_uart *) hdev->driver_data; state = (struct uart_state *) hu->tty->driver_data; bsi->uport = state->uart_port; } break; case HCI_DEV_UNREG: bluesleep_hdev = NULL; bsi->uport = NULL; break; case HCI_DEV_WRITE: bluesleep_outgoing_data(); break; } return NOTIFY_DONE; } /** * Handles transmission timer expiration. * @param data Not used. */ static void bluesleep_tx_timer_expire(unsigned long data) { unsigned long irq_flags; spin_lock_irqsave(&rw_lock, irq_flags); BT_DBG("Tx timer expired"); /* were we silent during the last timeout? */ if (!test_bit(BT_TXDATA, &flags)) { BT_DBG("Tx has been idle"); gpio_set_value(bsi->ext_wake, 1); bluesleep_tx_idle(); } else { BT_DBG("Tx data during last period"); mod_timer(&tx_timer, jiffies + (TX_TIMER_INTERVAL*HZ)); } /* clear the incoming data flag */ clear_bit(BT_TXDATA, &flags); spin_unlock_irqrestore(&rw_lock, irq_flags); } /** * Schedules a tasklet to run when receiving an interrupt on the * HOST_WAKE GPIO pin. * @param irq Not used. * @param dev_id Not used. */ static irqreturn_t bluesleep_hostwake_isr(int irq, void *dev_id) { /* schedule a tasklet to handle the change in the host wake line */ tasklet_schedule(&hostwake_task); return IRQ_HANDLED; } /** * Starts the Sleep-Mode Protocol on the Host. * @return On success, 0. On error, -1, and errno is set * appropriately. */ static int bluesleep_start(void) { int retval; unsigned long irq_flags; spin_lock_irqsave(&rw_lock, irq_flags); if (test_bit(BT_PROTO, &flags)) { spin_unlock_irqrestore(&rw_lock, irq_flags); return 0; } spin_unlock_irqrestore(&rw_lock, irq_flags); if (!atomic_dec_and_test(&open_count)) { atomic_inc(&open_count); return -EBUSY; } /* start the timer */ mod_timer(&tx_timer, jiffies + (TX_TIMER_INTERVAL*HZ)); /* assert BT_WAKE */ gpio_set_value(bsi->ext_wake, 0); retval = request_irq(bsi->host_wake_irq, bluesleep_hostwake_isr, IRQF_DISABLED | IRQF_TRIGGER_FALLING, "bluetooth hostwake", NULL); if (retval < 0) { BT_ERR("Couldn't acquire BT_HOST_WAKE IRQ"); goto fail; } retval = enable_irq_wake(bsi->host_wake_irq); if (retval < 0) { BT_ERR("Couldn't enable BT_HOST_WAKE as wakeup interrupt"); free_irq(bsi->host_wake_irq, NULL); goto fail; } set_bit(BT_PROTO, &flags); return 0; fail: del_timer(&tx_timer); atomic_inc(&open_count); return retval; } /** * Stops the Sleep-Mode Protocol on the Host. */ static void bluesleep_stop(void) { unsigned long irq_flags; spin_lock_irqsave(&rw_lock, irq_flags); if (!test_bit(BT_PROTO, &flags)) { spin_unlock_irqrestore(&rw_lock, irq_flags); return; } /* assert BT_WAKE */ gpio_set_value(bsi->ext_wake, 0); del_timer(&tx_timer); clear_bit(BT_PROTO, &flags); if (test_bit(BT_ASLEEP, &flags)) { clear_bit(BT_ASLEEP, &flags); hsuart_power(1); } atomic_inc(&open_count); spin_unlock_irqrestore(&rw_lock, irq_flags); if (disable_irq_wake(bsi->host_wake_irq)) BT_ERR("Couldn't disable hostwake IRQ wakeup mode\n"); free_irq(bsi->host_wake_irq, NULL); } /** * Read the BT_WAKE GPIO pin value via the proc interface. * When this function returns, page will contain a 1 if the * pin is high, 0 otherwise. * @param page Buffer for writing data. * @param start Not used. * @param offset Not used. * @param count Not used. * @param eof Whether or not there is more data to be read. * @param data Not used. * @return The number of bytes written. */ static int bluepower_read_proc_btwake(char *page, char **start, off_t offset, int count, int *eof, void *data) { *eof = 1; return sprintf(page, "btwake:%u\n", gpio_get_value(bsi->ext_wake)); } /** * Write the BT_WAKE GPIO pin value via the proc interface. * @param file Not used. * @param buffer The buffer to read from. * @param count The number of bytes to be written. * @param data Not used. * @return On success, the number of bytes written. On error, -1, and * errno is set appropriately. */ static int bluepower_write_proc_btwake(struct file *file, const char *buffer, unsigned long count, void *data) { char *buf; if (count < 1) return -EINVAL; buf = kmalloc(count, GFP_KERNEL); if (!buf) return -ENOMEM; if (copy_from_user(buf, buffer, count)) { kfree(buf); return -EFAULT; } if (buf[0] == '0') { gpio_set_value(bsi->ext_wake, 0); } else if (buf[0] == '1') { gpio_set_value(bsi->ext_wake, 1); } else { kfree(buf); return -EINVAL; } kfree(buf); return count; } /** * Read the BT_HOST_WAKE GPIO pin value via the proc interface. * When this function returns, page will contain a 1 if the pin * is high, 0 otherwise. * @param page Buffer for writing data. * @param start Not used. * @param offset Not used. * @param count Not used. * @param eof Whether or not there is more data to be read. * @param data Not used. * @return The number of bytes written. */ static int bluepower_read_proc_hostwake(char *page, char **start, off_t offset, int count, int *eof, void *data) { *eof = 1; return sprintf(page, "hostwake: %u \n", gpio_get_value(bsi->host_wake)); } /** * Read the low-power status of the Host via the proc interface. * When this function returns, page contains a 1 if the Host * is asleep, 0 otherwise. * @param page Buffer for writing data. * @param start Not used. * @param offset Not used. * @param count Not used. * @param eof Whether or not there is more data to be read. * @param data Not used. * @return The number of bytes written. */ static int bluesleep_read_proc_asleep(char *page, char **start, off_t offset, int count, int *eof, void *data) { unsigned int asleep; asleep = test_bit(BT_ASLEEP, &flags) ? 1 : 0; *eof = 1; return sprintf(page, "asleep: %u\n", asleep); } /** * Read the low-power protocol being used by the Host via the proc interface. * When this function returns, page will contain a 1 if the Host * is using the Sleep Mode Protocol, 0 otherwise. * @param page Buffer for writing data. * @param start Not used. * @param offset Not used. * @param count Not used. * @param eof Whether or not there is more data to be read. * @param data Not used. * @return The number of bytes written. */ static int bluesleep_read_proc_proto(char *page, char **start, off_t offset, int count, int *eof, void *data) { unsigned int proto; proto = test_bit(BT_PROTO, &flags) ? 1 : 0; *eof = 1; return sprintf(page, "proto: %u\n", proto); } /** * Modify the low-power protocol used by the Host via the proc interface. * @param file Not used. * @param buffer The buffer to read from. * @param count The number of bytes to be written. * @param data Not used. * @return On success, the number of bytes written. On error, -1, and * errno is set appropriately. */ static int bluesleep_write_proc_proto(struct file *file, const char *buffer, unsigned long count, void *data) { char proto; if (count < 1) return -EINVAL; if (copy_from_user(&proto, buffer, 1)) return -EFAULT; if (proto == '0') bluesleep_stop(); else bluesleep_start(); /* claim that we wrote everything */ return count; } static int __init bluesleep_probe(struct platform_device *pdev) { int ret; struct resource *res; bsi = kzalloc(sizeof(struct bluesleep_info), GFP_KERNEL); if (!bsi) return -ENOMEM; res = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio_host_wake"); if (!res) { BT_ERR("couldn't find host_wake gpio\n"); ret = -ENODEV; goto free_bsi; } bsi->host_wake = res->start; ret = gpio_request(bsi->host_wake, "bt_host_wake"); if (ret) goto free_bsi; ret = gpio_direction_input(bsi->host_wake); if (ret) goto free_bt_host_wake; res = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio_ext_wake"); if (!res) { BT_ERR("couldn't find ext_wake gpio\n"); ret = -ENODEV; goto free_bt_host_wake; } bsi->ext_wake = res->start; ret = gpio_request(bsi->ext_wake, "bt_ext_wake"); if (ret) goto free_bt_host_wake; /* assert bt wake */ ret = gpio_direction_output(bsi->ext_wake, 0); if (ret) goto free_bt_ext_wake; bsi->host_wake_irq = platform_get_irq_byname(pdev, "host_wake"); if (bsi->host_wake_irq < 0) { BT_ERR("couldn't find host_wake irq\n"); ret = -ENODEV; goto free_bt_ext_wake; } return 0; free_bt_ext_wake: gpio_free(bsi->ext_wake); free_bt_host_wake: gpio_free(bsi->host_wake); free_bsi: kfree(bsi); return ret; } static int bluesleep_remove(struct platform_device *pdev) { /* assert bt wake */ gpio_set_value(bsi->ext_wake, 0); if (test_bit(BT_PROTO, &flags)) { if (disable_irq_wake(bsi->host_wake_irq)) BT_ERR("Couldn't disable hostwake IRQ wakeup mode \n"); free_irq(bsi->host_wake_irq, NULL); del_timer(&tx_timer); if (test_bit(BT_ASLEEP, &flags)) hsuart_power(1); } gpio_free(bsi->host_wake); gpio_free(bsi->ext_wake); kfree(bsi); return 0; } static struct platform_driver bluesleep_driver = { .remove = bluesleep_remove, .driver = { .name = "bluesleep", .owner = THIS_MODULE, }, }; /** * Initializes the module. * @return On success, 0. On error, -1, and errno is set * appropriately. */ static int __init bluesleep_init(void) { int retval; struct proc_dir_entry *ent; BT_INFO("MSM Sleep Mode Driver Ver %s", VERSION); retval = platform_driver_probe(&bluesleep_driver, bluesleep_probe); if (retval) return retval; bluesleep_hdev = NULL; bluetooth_dir = proc_mkdir("bluetooth", NULL); if (bluetooth_dir == NULL) { BT_ERR("Unable to create /proc/bluetooth directory"); return -ENOMEM; } sleep_dir = proc_mkdir("sleep", bluetooth_dir); if (sleep_dir == NULL) { BT_ERR("Unable to create /proc/%s directory", PROC_DIR); return -ENOMEM; } /* Creating read/write "btwake" entry */ ent = create_proc_entry("btwake", 0, sleep_dir); if (ent == NULL) { BT_ERR("Unable to create /proc/%s/btwake entry", PROC_DIR); retval = -ENOMEM; goto fail; } ent->read_proc = bluepower_read_proc_btwake; ent->write_proc = bluepower_write_proc_btwake; /* read only proc entries */ if (create_proc_read_entry("hostwake", 0, sleep_dir, bluepower_read_proc_hostwake, NULL) == NULL) { BT_ERR("Unable to create /proc/%s/hostwake entry", PROC_DIR); retval = -ENOMEM; goto fail; } /* read/write proc entries */ ent = create_proc_entry("proto", 0, sleep_dir); if (ent == NULL) { BT_ERR("Unable to create /proc/%s/proto entry", PROC_DIR); retval = -ENOMEM; goto fail; } ent->read_proc = bluesleep_read_proc_proto; ent->write_proc = bluesleep_write_proc_proto; /* read only proc entries */ if (create_proc_read_entry("asleep", 0, sleep_dir, bluesleep_read_proc_asleep, NULL) == NULL) { BT_ERR("Unable to create /proc/%s/asleep entry", PROC_DIR); retval = -ENOMEM; goto fail; } flags = 0; /* clear all status bits */ /* Initialize spinlock. */ spin_lock_init(&rw_lock); /* Initialize timer */ init_timer(&tx_timer); tx_timer.function = bluesleep_tx_timer_expire; tx_timer.data = 0; /* initialize host wake tasklet */ tasklet_init(&hostwake_task, bluesleep_hostwake_task, 0); hci_register_notifier(&hci_event_nblock); return 0; fail: remove_proc_entry("asleep", sleep_dir); remove_proc_entry("proto", sleep_dir); remove_proc_entry("hostwake", sleep_dir); remove_proc_entry("btwake", sleep_dir); remove_proc_entry("sleep", bluetooth_dir); remove_proc_entry("bluetooth", 0); return retval; } /** * Cleans up the module. */ static void __exit bluesleep_exit(void) { hci_unregister_notifier(&hci_event_nblock); platform_driver_unregister(&bluesleep_driver); remove_proc_entry("asleep", sleep_dir); remove_proc_entry("proto", sleep_dir); remove_proc_entry("hostwake", sleep_dir); remove_proc_entry("btwake", sleep_dir); remove_proc_entry("sleep", bluetooth_dir); remove_proc_entry("bluetooth", 0); } module_init(bluesleep_init); module_exit(bluesleep_exit); MODULE_DESCRIPTION("Bluetooth Sleep Mode Driver ver %s " VERSION); #ifdef MODULE_LICENSE MODULE_LICENSE("GPL"); #endif