diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-parport.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-parport.c | 57 |
1 files changed, 29 insertions, 28 deletions
diff --git a/drivers/i2c/busses/i2c-parport.c b/drivers/i2c/busses/i2c-parport.c index 0eb1515541e..24565687ac9 100644 --- a/drivers/i2c/busses/i2c-parport.c +++ b/drivers/i2c/busses/i2c-parport.c @@ -1,14 +1,14 @@ /* ------------------------------------------------------------------------ * * i2c-parport.c I2C bus over parallel port * * ------------------------------------------------------------------------ * - Copyright (C) 2003-2010 Jean Delvare <khali@linux-fr.org> - + Copyright (C) 2003-2011 Jean Delvare <khali@linux-fr.org> + Based on older i2c-philips-par.c driver Copyright (C) 1995-2000 Simon G. Vogl With some changes from: Frodo Looijaard <frodol@dds.nl> Kyösti Mälkki <kmalkki@cc.hut.fi> - + This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or @@ -33,6 +33,8 @@ #include <linux/i2c-algo-bit.h> #include <linux/i2c-smbus.h> #include <linux/slab.h> +#include <linux/list.h> +#include <linux/mutex.h> #include "i2c-parport.h" /* ----- Device list ------------------------------------------------------ */ @@ -43,10 +45,11 @@ struct i2c_par { struct i2c_algo_bit_data algo_data; struct i2c_smbus_alert_setup alert_data; struct i2c_client *ara; - struct i2c_par *next; + struct list_head node; }; -static struct i2c_par *adapter_list; +static LIST_HEAD(adapter_list); +static DEFINE_MUTEX(adapter_list_lock); /* ----- Low-level parallel port access ----------------------------------- */ @@ -75,13 +78,13 @@ static unsigned char port_read_control(struct parport *p) return parport_read_control(p); } -static void (*port_write[])(struct parport *, unsigned char) = { +static void (* const port_write[])(struct parport *, unsigned char) = { port_write_data, NULL, port_write_control, }; -static unsigned char (*port_read[])(struct parport *) = { +static unsigned char (* const port_read[])(struct parport *) = { port_read_data, port_read_status, port_read_control, @@ -144,7 +147,7 @@ static const struct i2c_algo_bit_data parport_algo_data = { .getscl = parport_getscl, .udelay = 10, /* ~50 kbps */ .timeout = HZ, -}; +}; /* ----- I2c and parallel port call-back functions and structures --------- */ @@ -161,10 +164,10 @@ void i2c_parport_irq(void *data) "SMBus alert received but no ARA client!\n"); } -static void i2c_parport_attach (struct parport *port) +static void i2c_parport_attach(struct parport *port) { struct i2c_par *adapter; - + adapter = kzalloc(sizeof(struct i2c_par), GFP_KERNEL); if (adapter == NULL) { printk(KERN_ERR "i2c-parport: Failed to kzalloc\n"); @@ -177,7 +180,7 @@ static void i2c_parport_attach (struct parport *port) NULL, NULL, i2c_parport_irq, PARPORT_FLAG_EXCL, adapter); if (!adapter->pdev) { printk(KERN_ERR "i2c-parport: Unable to register with parport\n"); - goto ERROR0; + goto err_free; } /* Fill the rest of the structure */ @@ -197,7 +200,7 @@ static void i2c_parport_attach (struct parport *port) if (parport_claim_or_block(adapter->pdev) < 0) { printk(KERN_ERR "i2c-parport: Could not claim parallel port\n"); - goto ERROR1; + goto err_unregister; } /* Reset hardware to a sane state (SCL and SDA high) */ @@ -212,7 +215,7 @@ static void i2c_parport_attach (struct parport *port) if (i2c_bit_add_bus(&adapter->adapter) < 0) { printk(KERN_ERR "i2c-parport: Unable to register with I2C\n"); - goto ERROR1; + goto err_unregister; } /* Setup SMBus alert if supported */ @@ -228,24 +231,25 @@ static void i2c_parport_attach (struct parport *port) } /* Add the new adapter to the list */ - adapter->next = adapter_list; - adapter_list = adapter; - return; + mutex_lock(&adapter_list_lock); + list_add_tail(&adapter->node, &adapter_list); + mutex_unlock(&adapter_list_lock); + return; -ERROR1: + err_unregister: parport_release(adapter->pdev); parport_unregister_device(adapter->pdev); -ERROR0: + err_free: kfree(adapter); } -static void i2c_parport_detach (struct parport *port) +static void i2c_parport_detach(struct parport *port) { - struct i2c_par *adapter, *prev; + struct i2c_par *adapter, *_n; /* Walk the list */ - for (prev = NULL, adapter = adapter_list; adapter; - prev = adapter, adapter = adapter->next) { + mutex_lock(&adapter_list_lock); + list_for_each_entry_safe(adapter, _n, &adapter_list, node) { if (adapter->pdev->port == port) { if (adapter->ara) { parport_disable_irq(port); @@ -256,17 +260,14 @@ static void i2c_parport_detach (struct parport *port) /* Un-init if needed (power off...) */ if (adapter_parm[type].init.val) line_set(port, 0, &adapter_parm[type].init); - + parport_release(adapter->pdev); parport_unregister_device(adapter->pdev); - if (prev) - prev->next = adapter->next; - else - adapter_list = adapter->next; + list_del(&adapter->node); kfree(adapter); - return; } } + mutex_unlock(&adapter_list_lock); } static struct parport_driver i2c_parport_driver = { |