Dan Carpenter wrote on 2010-11-13: > This is a static checker patch and I don't have this hardware. > > This code is unusual because while I've often seen a double lock, this > is the first time I've seen code that takes a lock 11 times in a row. > I feel like I must have missed something. But I've looked very > carefully I don't see any way the original code is correct. Does > spi_sync() somehow release the lock in a way that I can't see? Even > if it does, the locking would still be wrong. This is simply bad code, and likely committed untested. > Signed-off-by: Dan Carpenter <error27@xxxxxxxxx> Acked-by: Michael Hennerich <michael.hennerich@xxxxxxxxxx> > --- > This should be easy to test for someone with the hardware. The ad9910 > driver should lock up on init. > > diff --git a/drivers/staging/iio/dds/ad9951.c > b/drivers/staging/iio/dds/ad9951.c index bc3beff..57eddf6 100644 --- > a/drivers/staging/iio/dds/ad9951.c +++ > b/drivers/staging/iio/dds/ad9951.c @@ -79,7 +79,6 @@ static ssize_t > ad9951_set_parameter(struct device *dev, > > xfer.len = 2; > xfer.tx_buf = &config->arr[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -89,7 +88,6 @@ static ssize_t ad9951_set_parameter(struct device *dev, > > xfer.len = 5; > xfer.tx_buf = &config->ftw0[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -99,7 +97,6 @@ static ssize_t ad9951_set_parameter(struct device *dev, > > xfer.len = 3; > xfer.tx_buf = &config->ftw1[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); @@ -143,8 > +140,6 @@ static void ad9951_init(struct ad9951_state *st) cfr[2] = > HSPD_SYNC; cfr[3] = 0; > - mutex_lock(&st->lock); > - > xfer.len = 4; > xfer.tx_buf = 𝔠 > diff --git a/drivers/staging/iio/dds/ad9910.c > b/drivers/staging/iio/dds/ad9910.c index c59b4079..e8fb75c 100644 --- > a/drivers/staging/iio/dds/ad9910.c +++ > b/drivers/staging/iio/dds/ad9910.c @@ -138,7 +138,6 @@ static ssize_t > ad9910_set_parameter(struct device *dev, > > xfer.len = 5; > xfer.tx_buf = &config->ioupd[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -148,7 +147,6 @@ static ssize_t ad9910_set_parameter(struct device > *dev, > > xfer.len = 5; > xfer.tx_buf = &config->ftw[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -158,7 +156,6 @@ static ssize_t ad9910_set_parameter(struct device > *dev, > > xfer.len = 3; > xfer.tx_buf = &config->pow[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -168,7 +165,6 @@ static ssize_t ad9910_set_parameter(struct device > *dev, > > xfer.len = 5; > xfer.tx_buf = &config->asf[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -178,7 +174,6 @@ static ssize_t ad9910_set_parameter(struct device > *dev, > > xfer.len = 5; > xfer.tx_buf = &config->multc[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -188,7 +183,6 @@ static ssize_t ad9910_set_parameter(struct device > *dev, > > xfer.len = 9; > xfer.tx_buf = &config->dig_rampl[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -198,7 +192,6 @@ static ssize_t ad9910_set_parameter(struct device > *dev, > > xfer.len = 9; > xfer.tx_buf = &config->dig_ramps[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -208,7 +201,6 @@ static ssize_t ad9910_set_parameter(struct device > *dev, > > xfer.len = 5; > xfer.tx_buf = &config->dig_rampr[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -218,25 +210,24 @@ static ssize_t ad9910_set_parameter(struct > device *dev, > > xfer.len = 9; > xfer.tx_buf = &config->sin_tonep0[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); ret = > spi_sync(st->sdev, &msg); if (ret) goto error_ret; + xfer.len = 9; > xfer.tx_buf = &config->sin_tonep1[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); ret = > spi_sync(st->sdev, &msg); if (ret) goto error_ret; + xfer.len = 9; > xfer.tx_buf = &config->sin_tonep2[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -245,43 +236,42 @@ static ssize_t ad9910_set_parameter(struct > device *dev, > goto error_ret; > xfer.len = 9; > xfer.tx_buf = &config->sin_tonep3[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); ret = > spi_sync(st->sdev, &msg); if (ret) goto error_ret; + xfer.len = 9; > xfer.tx_buf = &config->sin_tonep4[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); ret = > spi_sync(st->sdev, &msg); if (ret) goto error_ret; + xfer.len = 9; > xfer.tx_buf = &config->sin_tonep5[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); ret = > spi_sync(st->sdev, &msg); if (ret) goto error_ret; + xfer.len = 9; > xfer.tx_buf = &config->sin_tonep6[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); ret = > spi_sync(st->sdev, &msg); if (ret) goto error_ret; + xfer.len = 9; > xfer.tx_buf = &config->sin_tonep7[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); @@ -326,8 > +316,6 @@ static void ad9910_init(struct ad9910_state *st) cfr[3] = > TX_ENA | PDCLK_INV | PDCLK_ENB; cfr[4] = PARA_ENA; > - mutex_lock(&st->lock); > - > xfer.len = 5; > xfer.tx_buf = 𝔠 > @@ -343,8 +331,6 @@ static void ad9910_init(struct ad9910_state *st) > cfr[3] = REFCLK_RST | REFCLK_BYP; > cfr[4] = 0; > - mutex_lock(&st->lock); > - > xfer.len = 5; > xfer.tx_buf = 𝔠 > diff --git a/drivers/staging/iio/dds/ad9852.c > b/drivers/staging/iio/dds/ad9852.c index 0a41d25..594fb6a 100644 --- > a/drivers/staging/iio/dds/ad9852.c +++ > b/drivers/staging/iio/dds/ad9852.c @@ -86,7 +86,6 @@ static ssize_t > ad9852_set_parameter(struct device *dev, > > xfer.len = 3; > xfer.tx_buf = &config->phajst1[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -96,7 +95,6 @@ static ssize_t ad9852_set_parameter(struct device *dev, > > xfer.len = 6; > xfer.tx_buf = &config->fretun1[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -106,7 +104,6 @@ static ssize_t ad9852_set_parameter(struct device > *dev, > > xfer.len = 6; > xfer.tx_buf = &config->fretun2[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -116,7 +113,6 @@ static ssize_t ad9852_set_parameter(struct device > *dev, > > xfer.len = 6; > xfer.tx_buf = &config->dltafre[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -126,7 +122,6 @@ static ssize_t ad9852_set_parameter(struct device > *dev, > > xfer.len = 5; > xfer.tx_buf = &config->updtclk[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -136,7 +131,6 @@ static ssize_t ad9852_set_parameter(struct device > *dev, > > xfer.len = 4; > xfer.tx_buf = &config->ramprat[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -146,7 +140,6 @@ static ssize_t ad9852_set_parameter(struct device > *dev, > > xfer.len = 5; > xfer.tx_buf = &config->control[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -156,7 +149,6 @@ static ssize_t ad9852_set_parameter(struct device > *dev, > > xfer.len = 3; > xfer.tx_buf = &config->outpskm[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > @@ -166,16 +158,15 @@ static ssize_t ad9852_set_parameter(struct > device *dev, > > xfer.len = 2; > xfer.tx_buf = &config->outpskr[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); spi_message_add_tail(&xfer, &msg); ret = > spi_sync(st->sdev, &msg); if (ret) goto error_ret; + xfer.len = 3; > xfer.tx_buf = &config->daccntl[0]; > - mutex_lock(&st->lock); > > spi_message_init(&msg); > spi_message_add_tail(&xfer, &msg); > diff --git a/drivers/staging/iio/dds/ad9832.c > b/drivers/staging/iio/dds/ad9832.c index a4bb048..e911893 100644 --- > a/drivers/staging/iio/dds/ad9832.c +++ > b/drivers/staging/iio/dds/ad9832.c @@ -166,8 +166,6 @@ static void > ad9832_init(struct ad9832_state *st) > > config = 0x3 << 14; > - mutex_lock(&st->lock); > - > xfer.len = 2; > xfer.tx_buf = &config; Greetings, Michael -- Analog Devices GmbH Wilhelm-Wagenfeld-Str. 6 80807 Muenchen Sitz der Gesellschaft Muenchen, Registergericht Muenchen HRB 4036 Geschaeftsfuehrer Thomas Wessel, William A. 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