Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932422AbbFYKW2 (ORCPT ); Thu, 25 Jun 2015 06:22:28 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:39579 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752104AbbFYKDA (ORCPT ); Thu, 25 Jun 2015 06:03:00 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Paul Cercueil , Lars-Peter Clausen , Jonathan Cameron , Luis Henriques Subject: [PATCH 3.16.y-ckt 05/71] iio: adis16400: Fix burst mode Date: Thu, 25 Jun 2015 11:01:44 +0100 Message-Id: <1435226570-3669-6-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1435226570-3669-1-git-send-email-luis.henriques@canonical.com> References: <1435226570-3669-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3106 Lines: 82 3.16.7-ckt14 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Paul Cercueil commit 9df560350c90f3d3909fe653399b3584c9a17b61 upstream. There are a few issues with the burst mode support. For one we don't setup the rx buffer, so the buffer will never be filled and all samples will read as the zero. Furthermore the tx buffer has the wrong type, which means the driver sends the wrong command and not the right data is returned. The final issue is that in burst mode all channels are transferred. Hence the length of the transfer length should be the number of hardware channels * 2 bytes. Currently the driver uses indio_dev->scan_bytes for this. But if the timestamp channel is enabled the scan_bytes will be larger than the burst length. Fix this by just calculating the burst length based on the number of hardware channels. Signed-off-by: Paul Cercueil Signed-off-by: Lars-Peter Clausen Fixes: 5eda3550a3cc ("staging:iio:adis16400: Preallocate transfer message") Signed-off-by: Jonathan Cameron Signed-off-by: Luis Henriques --- drivers/iio/imu/adis16400_buffer.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/iio/imu/adis16400_buffer.c b/drivers/iio/imu/adis16400_buffer.c index 6e727ffe5262..629ae84d4e62 100644 --- a/drivers/iio/imu/adis16400_buffer.c +++ b/drivers/iio/imu/adis16400_buffer.c @@ -18,7 +18,8 @@ int adis16400_update_scan_mode(struct iio_dev *indio_dev, { struct adis16400_state *st = iio_priv(indio_dev); struct adis *adis = &st->adis; - uint16_t *tx; + unsigned int burst_length; + u8 *tx; if (st->variant->flags & ADIS16400_NO_BURST) return adis_update_scan_mode(indio_dev, scan_mask); @@ -26,26 +27,27 @@ int adis16400_update_scan_mode(struct iio_dev *indio_dev, kfree(adis->xfer); kfree(adis->buffer); + /* All but the timestamp channel */ + burst_length = (indio_dev->num_channels - 1) * sizeof(u16); + adis->xfer = kcalloc(2, sizeof(*adis->xfer), GFP_KERNEL); if (!adis->xfer) return -ENOMEM; - adis->buffer = kzalloc(indio_dev->scan_bytes + sizeof(u16), - GFP_KERNEL); + adis->buffer = kzalloc(burst_length + sizeof(u16), GFP_KERNEL); if (!adis->buffer) return -ENOMEM; - tx = adis->buffer + indio_dev->scan_bytes; - + tx = adis->buffer + burst_length; tx[0] = ADIS_READ_REG(ADIS16400_GLOB_CMD); tx[1] = 0; adis->xfer[0].tx_buf = tx; adis->xfer[0].bits_per_word = 8; adis->xfer[0].len = 2; - adis->xfer[1].tx_buf = tx; + adis->xfer[1].rx_buf = adis->buffer; adis->xfer[1].bits_per_word = 8; - adis->xfer[1].len = indio_dev->scan_bytes; + adis->xfer[1].len = burst_length; spi_message_init(&adis->msg); spi_message_add_tail(&adis->xfer[0], &adis->msg); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/