From patchwork Tue Jun 18 23:11:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Schmitt X-Patchwork-Id: 13703143 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 3CB201849F5; Tue, 18 Jun 2024 23:11:45 +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=1718752307; cv=none; b=QkvLsTDno0DkQMAQatCgiYuDxLaoO5Y74QM/yXSl6tYjxGAksVUR9JsQ4F1eOSn4uJT5tv7Dj1WhYE0Yy+tw7C4wXIp/ZBVQyPTOXA3jnJIUZRIU9vqCX6ROfYl1IBf4rs4W4KDCoAGQ+y2MtBviiZ7wwJE0BJJMuFjLf+vq/mY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718752307; c=relaxed/simple; bh=E0sPRQPXNtzkxzbOXNlwqNxDuZqt39oR9j6pBw9J1VM=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ORQGM/2NMbkoXhvE7KtUrcY0L6l+0DGrFnDxYOJTp3qzy8yVLiNMzL4gwU2mcRJPlds3nTpGidqCPGkhmS57mluEIMmq3RNcLX1z7VNYj+ipSOPaMQYtsYoICofcoNfNYaAJjY64I+d1693WzFwRrNeBe+Alu4c4+Ri9Dt/Cl/Y= 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=YIL7wLjX; 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="YIL7wLjX" Received: from pps.filterd (m0167089.ppops.net [127.0.0.1]) by mx0a-00128a01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 45ILXeSv028439; Tue, 18 Jun 2024 19:11:29 -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=j3giX IuN1pEHqX/58arefb4dOJNQT5mHyXJpGx+yV70=; b=YIL7wLjXXMnj72DGDXKSb f6wQqOFwZL+R/awbGlAux2R+ZQsWYVt8XbqfTZARs25LH2wsyWBh/2kLDWYaUia+ p8Kc+s5WIFdcZ9428EoTaamTGWG3ougHWMmuexkj5eOodMSlNj0hdw4dC/V18cgo skiXZqJqh5AgKUPOsOQg6t6+W830wsglOk+3hReBA9bWTUDST1oLZ/1VwKl5jcqU 3to04W2ggmNU1o4fjfQONvY0HxmovgpOcRflm2OHPMZ2hmMAD92KFPmlszSYmE7S 1QkpISDDt86FU6RTiCBmavGSbAc4XKFn++otbqbZS6XvBzb818VvoJVP5/LR9T8W A== Received: from nwd2mta3.analog.com ([137.71.173.56]) by mx0a-00128a01.pphosted.com (PPS) with ESMTPS id 3yuj8s87vb-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 18 Jun 2024 19:11:29 -0400 (EDT) Received: from ASHBMBX9.ad.analog.com (ASHBMBX9.ad.analog.com [10.64.17.10]) by nwd2mta3.analog.com (8.14.7/8.14.7) with ESMTP id 45INBSEg005870 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 18 Jun 2024 19:11:28 -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; Tue, 18 Jun 2024 19:11:27 -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; Tue, 18 Jun 2024 19:11:27 -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 45INBAXK021747; Tue, 18 Jun 2024 19:11:12 -0400 From: Marcelo Schmitt To: , , , , , , , , , CC: , , , Subject: [PATCH v4 2/6] spi: bitbang: Implement support for MOSI idle state configuration Date: Tue, 18 Jun 2024 20:11:08 -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-GUID: Qd1fkdthYYpqKBWdKGvns3ofJN1Yjiuf X-Proofpoint-ORIG-GUID: Qd1fkdthYYpqKBWdKGvns3ofJN1Yjiuf 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=2024-06-18_06,2024-06-17_01,2024-05-17_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 suspectscore=0 mlxscore=0 clxscore=1015 lowpriorityscore=0 phishscore=0 bulkscore=0 priorityscore=1501 malwarescore=0 spamscore=0 adultscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2405170001 definitions=main-2406180169 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 Signed-off-by: Marcelo Schmitt --- 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 */