From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 07B7AC433E1 for ; Sun, 2 Aug 2020 19:28:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EE673207BB for ; Sun, 2 Aug 2020 19:28:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=sang-engineering.com header.i=@sang-engineering.com header.b="rC//axUx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726883AbgHBT2w (ORCPT ); Sun, 2 Aug 2020 15:28:52 -0400 Received: from www.zeus03.de ([194.117.254.33]:54134 "EHLO mail.zeus03.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725910AbgHBT2v (ORCPT ); Sun, 2 Aug 2020 15:28:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple; d=sang-engineering.com; h= from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; s=k1; bh=iviGTYrF2GwjFPXyaMWHzGc64c2 XIQsPMpnT7p1fQeA=; b=rC//axUxhcrtdsPjRhi6OciHS3ssbJvKxwZsO0vv1TY 01Zx9rgeyRdUq3IDnExePmwkiHNdvoIKAu5LRECYhhld1KX/6E2gHwLOojff8k+d jwkv61OwFAnIp6v/hu6gdxuWjkqXqq+e9AH5CDXF/Y/YO4xePvsg+r8ydwMzTOX0 = Received: (qmail 2167675 invoked from network); 2 Aug 2020 21:28:49 +0200 Received: by mail.zeus03.de with ESMTPSA (TLS_AES_256_GCM_SHA384 encrypted, authenticated); 2 Aug 2020 21:28:49 +0200 X-UD-Smtp-Session: l3s3148p1@sJQMCOqrKJNQT+F6 From: Wolfram Sang To: linux-i2c@vger.kernel.org Cc: linux-renesas-soc@vger.kernel.org, Daniel Stodden , Wolfram Sang Subject: [PATCH i2c-tools] i2ctransfer: add support for I2C_M_RECV_LEN Date: Sun, 2 Aug 2020 21:28:42 +0200 Message-Id: <20200802192842.13527-1-wsa+renesas@sang-engineering.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Strictly spoken, this is for emulating SMBus transfers, not I2C. But hey, we still want to test devices supporting these transfers. Signed-off-by: Wolfram Sang --- I created this to be able to play around with I2C_M_RECV_LEN and with SMBUS2 and SMBUS3 max block sizes. Tested with a Renesas Lager board and my slave-testunit hacked with SMBus block transfer support (to be upstreamed later). Fun fact: printing the correct length in the output took longer than implementing the actual functionality. tools/i2ctransfer.8 | 1 + tools/i2ctransfer.c | 42 +++++++++++++++++++++++++++++++----------- 2 files changed, 32 insertions(+), 11 deletions(-) diff --git a/tools/i2ctransfer.8 b/tools/i2ctransfer.8 index d16e34e..152d20d 100644 --- a/tools/i2ctransfer.8 +++ b/tools/i2ctransfer.8 @@ -91,6 +91,7 @@ specifies if the message is read or write .B specifies the number of bytes read or written in this message. It is parsed as an unsigned 16 bit integer, but note that the Linux Kernel applies an additional upper limit (8192 as of v4.10). +For read messages to targets which support SMBus Block transactions, it can also be '?', then the target will determine the length. .TP .B [@address] specifies the 7-bit address of the chip to be accessed for this message, and is an integer. diff --git a/tools/i2ctransfer.c b/tools/i2ctransfer.c index 7b95d48..2b8a3fb 100644 --- a/tools/i2ctransfer.c +++ b/tools/i2ctransfer.c @@ -45,7 +45,8 @@ static void help(void) "Usage: i2ctransfer [-f] [-y] [-v] [-V] [-a] I2CBUS DESC [DATA] [DESC [DATA]]...\n" " I2CBUS is an integer or an I2C bus name\n" " DESC describes the transfer in the form: {r|w}LENGTH[@address]\n" - " 1) read/write-flag 2) LENGTH (range 0-65535) 3) I2C address (use last one if omitted)\n" + " 1) read/write-flag 2) LENGTH (range 0-65535, or '?')\n" + " 3) I2C address (use last one if omitted)\n" " DATA are LENGTH bytes for a write message. They can be shortened by a suffix:\n" " = (keep value constant until LENGTH)\n" " + (increase value by 1 until LENGTH)\n" @@ -84,17 +85,24 @@ static void print_msgs(struct i2c_msg *msgs, __u32 nmsgs, unsigned flags) for (i = 0; i < nmsgs; i++) { int read = msgs[i].flags & I2C_M_RD; + int recv_len = msgs[i].flags & I2C_M_RECV_LEN; int print_buf = (read && (flags & PRINT_READ_BUF)) || (!read && (flags & PRINT_WRITE_BUF)); - - if (flags & PRINT_HEADER) - fprintf(output, "msg %u: addr 0x%02x, %s, len %u", - i, msgs[i].addr, read ? "read" : "write", msgs[i].len); + __u16 len = recv_len ? msgs[i].buf[0] + 1 : msgs[i].len; + + if (flags & PRINT_HEADER) { + fprintf(output, "msg %u: addr 0x%02x, %s, len ", + i, msgs[i].addr, read ? "read" : "write"); + if (!recv_len || flags & PRINT_READ_BUF) + fprintf(output, "%u", len); + else + fprintf(output, "TBD"); + } if (msgs[i].len && print_buf) { if (flags & PRINT_HEADER) fprintf(output, ", buf "); - for (j = 0; j < msgs[i].len - 1; j++) + for (j = 0; j < len - 1; j++) fprintf(output, "0x%02x ", msgs[i].buf[j]); /* Print final byte with newline */ fprintf(output, "0x%02x\n", msgs[i].buf[j]); @@ -192,13 +200,23 @@ int main(int argc, char *argv[]) goto err_out_with_arg; } - len = strtoul(arg_ptr, &end, 0); - if (len > 0xffff || arg_ptr == end) { - fprintf(stderr, "Error: Length invalid\n"); - goto err_out_with_arg; + if (*arg_ptr == '?') { + if (!(flags & I2C_M_RD)) { + fprintf(stderr, "Error: variable length not allowed with write\n"); + goto err_out_with_arg; + } + len = 256; /* SMBUS3_MAX_BLOCK_LEN + 1 */ + flags |= I2C_M_RECV_LEN; + arg_ptr++; + } else { + len = strtoul(arg_ptr, &end, 0); + if (len > 0xffff || arg_ptr == end) { + fprintf(stderr, "Error: Length invalid\n"); + goto err_out_with_arg; + } + arg_ptr = end; } - arg_ptr = end; if (*arg_ptr) { if (*arg_ptr++ != '@') { fprintf(stderr, "Error: Unknown separator after length\n"); @@ -237,6 +255,8 @@ int main(int argc, char *argv[]) } memset(buf, 0, len); msgs[nmsgs].buf = buf; + if (flags & I2C_M_RECV_LEN) + buf[0] = 1; /* number of extra bytes */ } if (flags & I2C_M_RD || len == 0) { -- 2.27.0