From 9faa310f2b813bad7682120d37ac760db14eec93 Mon Sep 17 00:00:00 2001 From: Ksenija Stanojevic Date: Tue, 13 Oct 2015 19:08:03 +0200 Subject: [PATCH] Staging: comedi: dt9812: Use mutex instead of semaphore Replace binary semaphore with mutex. Mutex also gives better performance than semaphore. Signed-off-by: Ksenija Stanojevic Reviewed-by: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/dt9812.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/drivers/staging/comedi/drivers/dt9812.c b/drivers/staging/comedi/drivers/dt9812.c index 0a4ee8b..3295bb4 100644 --- a/drivers/staging/comedi/drivers/dt9812.c +++ b/drivers/staging/comedi/drivers/dt9812.c @@ -233,7 +233,7 @@ struct dt9812_usb_cmd { }; struct dt9812_private { - struct semaphore sem; + struct mutex mut; struct { __u8 addr; size_t size; @@ -335,7 +335,7 @@ static int dt9812_digital_in(struct comedi_device *dev, u8 *bits) u8 value[2]; int ret; - down(&devpriv->sem); + mutex_lock(&devpriv->mut); ret = dt9812_read_multiple_registers(dev, 2, reg, value); if (ret == 0) { /* @@ -345,7 +345,7 @@ static int dt9812_digital_in(struct comedi_device *dev, u8 *bits) */ *bits = (value[0] & 0x7f) | ((value[1] & 0x08) << 4); } - up(&devpriv->sem); + mutex_unlock(&devpriv->mut); return ret; } @@ -357,9 +357,9 @@ static int dt9812_digital_out(struct comedi_device *dev, u8 bits) u8 value[1] = { bits }; int ret; - down(&devpriv->sem); + mutex_lock(&devpriv->mut); ret = dt9812_write_multiple_registers(dev, 1, reg, value); - up(&devpriv->sem); + mutex_unlock(&devpriv->mut); return ret; } @@ -444,7 +444,7 @@ static int dt9812_analog_in(struct comedi_device *dev, u8 val[3]; int ret; - down(&devpriv->sem); + mutex_lock(&devpriv->mut); /* 1 select the gain */ dt9812_configure_gain(dev, &rmw[0], gain); @@ -493,7 +493,7 @@ static int dt9812_analog_in(struct comedi_device *dev, } exit: - up(&devpriv->sem); + mutex_unlock(&devpriv->mut); return ret; } @@ -504,7 +504,7 @@ static int dt9812_analog_out(struct comedi_device *dev, int channel, u16 value) struct dt9812_rmw_byte rmw[3]; int ret; - down(&devpriv->sem); + mutex_lock(&devpriv->mut); switch (channel) { case 0: @@ -543,7 +543,7 @@ static int dt9812_analog_out(struct comedi_device *dev, int channel, u16 value) } ret = dt9812_rmw_multiple_registers(dev, 3, rmw); - up(&devpriv->sem); + mutex_unlock(&devpriv->mut); return ret; } @@ -606,9 +606,9 @@ static int dt9812_ao_insn_read(struct comedi_device *dev, struct dt9812_private *devpriv = dev->private; int ret; - down(&devpriv->sem); + mutex_lock(&devpriv->mut); ret = comedi_readback_insn_read(dev, s, insn, data); - up(&devpriv->sem); + mutex_unlock(&devpriv->mut); return ret; } @@ -772,7 +772,7 @@ static int dt9812_auto_attach(struct comedi_device *dev, if (!devpriv) return -ENOMEM; - sema_init(&devpriv->sem, 1); + mutex_init(&devpriv->mut); usb_set_intfdata(intf, devpriv); ret = dt9812_find_endpoints(dev); @@ -844,11 +844,11 @@ static void dt9812_detach(struct comedi_device *dev) if (!devpriv) return; - down(&devpriv->sem); + mutex_lock(&devpriv->mut); usb_set_intfdata(intf, NULL); - up(&devpriv->sem); + mutex_unlock(&devpriv->mut); } static struct comedi_driver dt9812_driver = { -- 2.7.4