Commit 31e2d42a authored by Sergiu Cuciurean's avatar Sergiu Cuciurean Committed by Jonathan Cameron
Browse files

iio: adc: spear_adc: Replace indio_dev->mlock with own device lock 

As part of the general cleanup of indio_dev->mlock, this change replaces
it with a local lock on the device's state structure.

This is part of a bigger cleanup.
Link: https://lore.kernel.org/linux-iio/CA+U=Dsoo6YABe5ODLp+eFNPGFDjk5ZeQEceGkqjxXcVEhLWubw@mail.gmail.com/



Signed-off-by: default avatarSergiu Cuciurean <sergiu.cuciurean@analog.com>
Signed-off-by: default avatarMircea Caprioru <mircea.caprioru@analog.com>
Link: https://lore.kernel.org/r/20200928131333.36646-1-mircea.caprioru@analog.com


Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent 2a94469f

drivers/iio/adc/spear_adc.c

+16 −4
Original line number Diff line number Diff line
@@ -75,6 +75,15 @@ struct spear_adc_state { 
	struct adc_regs_spear6xx __iomem *adc_base_spear6xx;

	struct clk *clk;

	struct completion completion;

	/*

	 * Lock to protect the device state during a potential concurrent

	 * read access from userspace. Reading a raw value requires a sequence

	 * of register writes, then a wait for a completion callback,

	 * and finally a register read, during which userspace could issue

	 * another read request. This lock protects a read access from

	 * ocurring before another one has finished.

	 */

	struct mutex lock;

	u32 current_clk;

	u32 sampling_freq;

	u32 avg_samples;
@@ -146,7 +155,7 @@ static int spear_adc_read_raw(struct iio_dev *indio_dev, 


	switch (mask) {

	case IIO_CHAN_INFO_RAW:

		mutex_lock(&indio_dev->mlock);

		mutex_lock(&st->lock);



		status = SPEAR_ADC_STATUS_CHANNEL_NUM(chan->channel) |

			SPEAR_ADC_STATUS_AVG_SAMPLE(st->avg_samples) |
@@ -159,7 +168,7 @@ static int spear_adc_read_raw(struct iio_dev *indio_dev, 
		wait_for_completion(&st->completion); /* set by ISR */

		*val = st->value;



		mutex_unlock(&indio_dev->mlock);

		mutex_unlock(&st->lock);



		return IIO_VAL_INT;
@@ -187,7 +196,7 @@ static int spear_adc_write_raw(struct iio_dev *indio_dev, 
	if (mask != IIO_CHAN_INFO_SAMP_FREQ)

		return -EINVAL;



	mutex_lock(&indio_dev->mlock);

	mutex_lock(&st->lock);



	if ((val < SPEAR_ADC_CLK_MIN) ||

	    (val > SPEAR_ADC_CLK_MAX) ||
@@ -199,7 +208,7 @@ static int spear_adc_write_raw(struct iio_dev *indio_dev, 
	spear_adc_set_clk(st, val);



out:

	mutex_unlock(&indio_dev->mlock);

	mutex_unlock(&st->lock);

	return ret;

}
@@ -271,6 +280,9 @@ static int spear_adc_probe(struct platform_device *pdev) 
	}



	st = iio_priv(indio_dev);



	mutex_init(&st->lock);



	st->np = np;



	/*