From patchwork Sat Jun 29 19:05:05 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Schmitt X-Patchwork-Id: 808633 Received: from mx0a-00128a01.pphosted.com (mx0a-00128a01.pphosted.com [148.163.135.77]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E139A1327E5; Sat, 29 Jun 2024 19:05:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.135.77 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719687944; cv=none; b=EWOyUUt9sQqBQMBPNSCTstC/oSnRHFParvZJQ9HB/Xjp5p+n1YuhEmWpYc6hOz0Z/p7/i3/3v3rR9rJFdGavWjdNpgdvH9xlQHK07A+mLLyPxLGIYkpDrPusnjNpbtjNnW/eMSY6n3VHvX+w9VLej8egtkQ6yezFljYhVn2cpRk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719687944; c=relaxed/simple; bh=5emOr23gfJXP7GvQKnWdrmTvh5WM/hJIvc5AVGKVh9o=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=N2VmKZZUqbReOB9l81dO0NyPdTUyiT85kmgqi75s0y1FhmnrHL0gon/qsYVIxY5dhNuY8T+9X7XEW3pP7FN3rOS6TcvptLDRTaL+i8v+PlOfMdO6hk4aWCt/7jps3W8uVkudpnneNo81tqPJHgkTVOjuBQZO8eh7pgifXV/3qjg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=analog.com; spf=pass smtp.mailfrom=analog.com; dkim=pass (2048-bit key) header.d=analog.com header.i=@analog.com header.b=PphVo3OY; arc=none smtp.client-ip=148.163.135.77 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=analog.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=analog.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=analog.com header.i=@analog.com header.b="PphVo3OY" Received: from pps.filterd (m0167088.ppops.net [127.0.0.1]) by mx0a-00128a01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 45TIFobB002097; Sat, 29 Jun 2024 15:05:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=analog.com; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=DKIM; bh=qrMN5 yTUSTr/EDaXETZ+Q0tqWERqiqfvL9ZDcnpTHEY=; b=PphVo3OYrGvT+ef366DiU Zrk+izoBjAQBFck3wUUzDmW0vKfDaPjK6aEujSmWH2j7DBMTMaoMo6KiT7MNNyk8 WWgPRcnZrYtKyA9m9TUtI9N5ykrn2uaeSmIu7ld4fMB+nSmI6WSPvKTyek6LR3jm pm4O2TuwP5wnWiWjj4I+yJzVI/V2NBDyCfCPZ88ZRi3C/7PWEbOw0G/aGFvwfF5d 5h90HhIQGKWbeXjS9rnbsTlQUh7thjm59eDmrQaduFudjYz3woHwljZx903S/P+4 rwh4UYHYxyMMI1ziW+lsYD+mFIvLA0X5mNNWcoNNIZJnR4g2jori/qvQw3uuBzdD w== Received: from nwd2mta4.analog.com ([137.71.173.58]) by mx0a-00128a01.pphosted.com (PPS) with ESMTPS id 402c43has0-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 29 Jun 2024 15:05:27 -0400 (EDT) Received: from ASHBMBX9.ad.analog.com (ASHBMBX9.ad.analog.com [10.64.17.10]) by nwd2mta4.analog.com (8.14.7/8.14.7) with ESMTP id 45TJ5PDj046834 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Sat, 29 Jun 2024 15:05:25 -0400 Received: from ASHBMBX8.ad.analog.com (10.64.17.5) by ASHBMBX9.ad.analog.com (10.64.17.10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.14; Sat, 29 Jun 2024 15:05:24 -0400 Received: from zeus.spd.analog.com (10.66.68.11) by ashbmbx8.ad.analog.com (10.64.17.5) with Microsoft SMTP Server id 15.2.986.14 via Frontend Transport; Sat, 29 Jun 2024 15:05:24 -0400 Received: from work.ad.analog.com (HYB-hERzalRezfV.ad.analog.com [10.65.205.129]) by zeus.spd.analog.com (8.15.1/8.15.1) with ESMTP id 45TJ568e001368; Sat, 29 Jun 2024 15:05:09 -0400 From: Marcelo Schmitt To: , , , , , , , , , , CC: , , , , Subject: [PATCH v6 2/7] spi: bitbang: Implement support for MOSI idle state configuration Date: Sat, 29 Jun 2024 16:05:05 -0300 Message-ID: X-Mailer: git-send-email 2.30.2 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-spi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ADIRuleOP-NewSCL: Rule Triggered X-Proofpoint-ORIG-GUID: HEICcfU56oDr2dq8OrpARTEFE-gerFyA X-Proofpoint-GUID: HEICcfU56oDr2dq8OrpARTEFE-gerFyA X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.680,FMLib:17.12.28.16 definitions=2024-06-29_08,2024-06-28_01,2024-05-17_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 lowpriorityscore=0 suspectscore=0 adultscore=0 bulkscore=0 malwarescore=0 spamscore=0 impostorscore=0 mlxscore=0 clxscore=1015 phishscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2406140001 definitions=main-2406290138 Some SPI peripherals may require strict MOSI line state when the controller is not clocking out data. Implement support for MOSI idle state configuration (low or high) by setting the data output line level on controller setup and after transfers. Bitbang operations now call controller specific set_mosi_idle() call back to set MOSI to its idle state. The MOSI line is kept at its idle state if no tx buffer is provided. Acked-by: Nuno Sa Reviewed-by: David Lechner Signed-off-by: Marcelo Schmitt Reviewed-by: Jonathan Cameron --- drivers/spi/spi-bitbang.c | 24 ++++++++++++++++++++++++ include/linux/spi/spi_bitbang.h | 1 + 2 files changed, 25 insertions(+) diff --git a/drivers/spi/spi-bitbang.c b/drivers/spi/spi-bitbang.c index ca5cc67555c5..8cc522bf444c 100644 --- a/drivers/spi/spi-bitbang.c +++ b/drivers/spi/spi-bitbang.c @@ -63,21 +63,28 @@ static unsigned bitbang_txrx_8( unsigned flags ) { + struct spi_bitbang *bitbang; unsigned bits = t->bits_per_word; unsigned count = t->len; const u8 *tx = t->tx_buf; u8 *rx = t->rx_buf; + bitbang = spi_controller_get_devdata(spi->controller); while (likely(count > 0)) { u8 word = 0; if (tx) word = *tx++; + else + word = spi->mode & SPI_MOSI_IDLE_HIGH ? 0xFF : 0; word = txrx_word(spi, ns, word, bits, flags); if (rx) *rx++ = word; count -= 1; } + if (bitbang->set_mosi_idle) + bitbang->set_mosi_idle(spi); + return t->len - count; } @@ -92,21 +99,28 @@ static unsigned bitbang_txrx_16( unsigned flags ) { + struct spi_bitbang *bitbang; unsigned bits = t->bits_per_word; unsigned count = t->len; const u16 *tx = t->tx_buf; u16 *rx = t->rx_buf; + bitbang = spi_controller_get_devdata(spi->controller); while (likely(count > 1)) { u16 word = 0; if (tx) word = *tx++; + else + word = spi->mode & SPI_MOSI_IDLE_HIGH ? 0xFFFF : 0; word = txrx_word(spi, ns, word, bits, flags); if (rx) *rx++ = word; count -= 2; } + if (bitbang->set_mosi_idle) + bitbang->set_mosi_idle(spi); + return t->len - count; } @@ -121,21 +135,28 @@ static unsigned bitbang_txrx_32( unsigned flags ) { + struct spi_bitbang *bitbang; unsigned bits = t->bits_per_word; unsigned count = t->len; const u32 *tx = t->tx_buf; u32 *rx = t->rx_buf; + bitbang = spi_controller_get_devdata(spi->controller); while (likely(count > 3)) { u32 word = 0; if (tx) word = *tx++; + else + word = spi->mode & SPI_MOSI_IDLE_HIGH ? 0xFFFFFFFF : 0; word = txrx_word(spi, ns, word, bits, flags); if (rx) *rx++ = word; count -= 4; } + if (bitbang->set_mosi_idle) + bitbang->set_mosi_idle(spi); + return t->len - count; } @@ -211,6 +232,9 @@ int spi_bitbang_setup(struct spi_device *spi) goto err_free; } + if (bitbang->set_mosi_idle) + bitbang->set_mosi_idle(spi); + dev_dbg(&spi->dev, "%s, %u nsec/bit\n", __func__, 2 * cs->nsecs); return 0; diff --git a/include/linux/spi/spi_bitbang.h b/include/linux/spi/spi_bitbang.h index b930eca2ef7b..1a54b593c691 100644 --- a/include/linux/spi/spi_bitbang.h +++ b/include/linux/spi/spi_bitbang.h @@ -22,6 +22,7 @@ struct spi_bitbang { #define BITBANG_CS_ACTIVE 1 /* normally nCS, active low */ #define BITBANG_CS_INACTIVE 0 + void (*set_mosi_idle)(struct spi_device *spi); /* txrx_bufs() may handle dma mapping for transfers that don't * already have one (transfer.{tx,rx}_dma is zero), or use PIO */