From patchwork Wed Aug 17 10:56:43 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Artur Rojek X-Patchwork-Id: 12945721 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 71672C32773 for ; Wed, 17 Aug 2022 10:57:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239060AbiHQK5a (ORCPT ); Wed, 17 Aug 2022 06:57:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239085AbiHQK50 (ORCPT ); Wed, 17 Aug 2022 06:57:26 -0400 Received: from relay12.mail.gandi.net (relay12.mail.gandi.net [217.70.178.232]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 56439647E8; Wed, 17 Aug 2022 03:57:25 -0700 (PDT) Received: (Authenticated sender: contact@artur-rojek.eu) by mail.gandi.net (Postfix) with ESMTPSA id 9002B200009; Wed, 17 Aug 2022 10:57:22 +0000 (UTC) From: Artur Rojek To: Paul Cercueil , Jonathan Cameron , Dmitry Torokhov , Chris Morgan Cc: linux-mips@vger.kernel.org, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, Artur Rojek Subject: [PATCH 4/4] input: joystick: Fix buffer data parsing Date: Wed, 17 Aug 2022 12:56:43 +0200 Message-Id: <20220817105643.95710-5-contact@artur-rojek.eu> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220817105643.95710-1-contact@artur-rojek.eu> References: <20220817105643.95710-1-contact@artur-rojek.eu> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org Don't try to access buffer data of a channel by its scan index. Instead, use the newly introduced `iio_find_channel_offset_in_buffer` to get the correct data offset. The scan index of a channel does not represent its position in a buffer, as the buffer will contain data for enabled channels only, affecting data offsets and alignment. Fixes: 2c2b364fddd5 ("Input: joystick - add ADC attached joystick driver.") Reported-by: Chris Morgan Tested-by: Paul Cercueil Signed-off-by: Artur Rojek --- drivers/input/joystick/adc-joystick.c | 26 +++++++++++++++++--------- 1 file changed, 17 insertions(+), 9 deletions(-) diff --git a/drivers/input/joystick/adc-joystick.c b/drivers/input/joystick/adc-joystick.c index c0deff5d4282..aed853ebe1d1 100644 --- a/drivers/input/joystick/adc-joystick.c +++ b/drivers/input/joystick/adc-joystick.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include #include @@ -46,36 +47,43 @@ static void adc_joystick_poll(struct input_dev *input) static int adc_joystick_handle(const void *data, void *private) { struct adc_joystick *joy = private; + struct iio_buffer *buffer; enum iio_endian endianness; - int bytes, msb, val, idx, i; - const u16 *data_u16; + int bytes, msb, val, off; + const u8 *chan_data; + unsigned int i; bool sign; bytes = joy->chans[0].channel->scan_type.storagebits >> 3; for (i = 0; i < joy->num_chans; ++i) { - idx = joy->chans[i].channel->scan_index; endianness = joy->chans[i].channel->scan_type.endianness; msb = joy->chans[i].channel->scan_type.realbits - 1; sign = tolower(joy->chans[i].channel->scan_type.sign) == 's'; + buffer = iio_channel_cb_get_iio_buffer(joy->buffer); + off = iio_find_channel_offset_in_buffer(joy->chans[i].indio_dev, + joy->chans[i].channel, + buffer); + if (off < 0) + return off; + + chan_data = (const u8 *)data + off; switch (bytes) { case 1: - val = ((const u8 *)data)[idx]; + val = *chan_data; break; case 2: - data_u16 = (const u16 *)data + idx; - /* * Data is aligned to the sample size by IIO core. * Call `get_unaligned_xe16` to hide type casting. */ if (endianness == IIO_BE) - val = get_unaligned_be16(data_u16); + val = get_unaligned_be16(chan_data); else if (endianness == IIO_LE) - val = get_unaligned_le16(data_u16); + val = get_unaligned_le16(chan_data); else /* IIO_CPU */ - val = *data_u16; + val = *(const u16 *)chan_data; break; default: return -EINVAL;