From patchwork Sun May 10 09:50:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Serge Semin X-Patchwork-Id: 11539111 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 22AE915E6 for ; Sun, 10 May 2020 09:50:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0EBA82137B for ; Sun, 10 May 2020 09:50:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727784AbgEJJu2 (ORCPT ); Sun, 10 May 2020 05:50:28 -0400 Received: from mail.baikalelectronics.com ([87.245.175.226]:45878 "EHLO mail.baikalelectronics.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726104AbgEJJu2 (ORCPT ); Sun, 10 May 2020 05:50:28 -0400 Received: from localhost (unknown [127.0.0.1]) by mail.baikalelectronics.ru (Postfix) with ESMTP id CE7A18030875; Sun, 10 May 2020 09:50:24 +0000 (UTC) X-Virus-Scanned: amavisd-new at baikalelectronics.ru Received: from mail.baikalelectronics.ru ([127.0.0.1]) by localhost (mail.baikalelectronics.ru [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id OfwJvFjXcLcw; Sun, 10 May 2020 12:50:24 +0300 (MSK) From: Serge Semin To: Jarkko Nikula , Rob Herring , Frank Rowand CC: Serge Semin , Serge Semin , Alexey Malahov , Thomas Bogendoerfer , Paul Burton , Ralf Baechle , Mika Westerberg , Wolfram Sang , , , Rob Herring , Greg Kroah-Hartman , Richard Fontana , Thomas Gleixner , , Subject: [PATCH v2 01/12] scripts/dtc: check: Add 10bit/slave i2c reg flags support Date: Sun, 10 May 2020 12:50:07 +0300 Message-ID: <20200510095019.20981-2-Sergey.Semin@baikalelectronics.ru> In-Reply-To: <20200510095019.20981-1-Sergey.Semin@baikalelectronics.ru> References: <20200306132001.1B875803087C@mail.baikalelectronics.ru> <20200510095019.20981-1-Sergey.Semin@baikalelectronics.ru> MIME-Version: 1.0 X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org Recently the I2C-controllers slave interface support was added to the kernel I2C subsystem. In this case Linux can be used as, for example, a I2C EEPROM machine. See [1] for details. Other than instantiating the EEPROM-slave device from user-space there is a way to declare the device in dts. In this case firstly the I2C bus controller must support the slave interface. Secondly I2C-slave sub-node of that controller must have "reg"-property with flag I2C_OWN_SLAVE_ADDRESS set (flag is declared in [2]). That flag is declared as (1 << 30), which when set makes dtc unhappy about too big address set for a I2C-slave: Warning (i2c_bus_reg): /example-2/i2c@1120000/eeprom@64: I2C bus unit address format error, expected "40000064" Warning (i2c_bus_reg): /example-2/i2c@1120000/eeprom@64:reg: I2C address must be less than 10-bits, got "0x40000064" Similar problem would have happened if we had set the 10-bit address flag I2C_TEN_BIT_ADDRESS in the "reg"-property. In order to fix the problem we suggest to alter the I2C-bus reg-check algorithm, so one would be aware of the upper bits set. Normally if no flag specified, the 7-bit address is expected in the "reg"-property. If I2C_TEN_BIT_ADDRESS is set, then the 10-bit address check will be performed. The I2C_OWN_SLAVE_ADDRESS flag will be just ignored. [1] Documentation/i2c/slave-interface.rst [2] include/dt-bindings/i2c/i2c.h Signed-off-by: Serge Semin Cc: Alexey Malahov Cc: Thomas Bogendoerfer Cc: Paul Burton Cc: Ralf Baechle Cc: Mika Westerberg Cc: Wolfram Sang Cc: linux-mips@vger.kernel.org Cc: linux-i2c@vger.kernel.org --- scripts/dtc/checks.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/scripts/dtc/checks.c b/scripts/dtc/checks.c index 4b3c486f1399..6321fc5b7404 100644 --- a/scripts/dtc/checks.c +++ b/scripts/dtc/checks.c @@ -1028,6 +1028,7 @@ static void check_i2c_bus_reg(struct check *c, struct dt_info *dti, struct node const char *unitname = get_unitname(node); char unit_addr[17]; uint32_t reg = 0; + uint32_t addr; int len; cell_t *cells = NULL; @@ -1044,17 +1045,21 @@ static void check_i2c_bus_reg(struct check *c, struct dt_info *dti, struct node } reg = fdt32_to_cpu(*cells); - snprintf(unit_addr, sizeof(unit_addr), "%x", reg); + addr = reg & 0x3FFFFFFFU; + snprintf(unit_addr, sizeof(unit_addr), "%x", addr); if (!streq(unitname, unit_addr)) FAIL(c, dti, node, "I2C bus unit address format error, expected \"%s\"", unit_addr); for (len = prop->val.len; len > 0; len -= 4) { reg = fdt32_to_cpu(*(cells++)); - if (reg > 0x3ff) + addr = reg & 0x3FFFFFFFU; + if ((reg & (1 << 31)) && addr > 0x3ff) FAIL_PROP(c, dti, node, prop, "I2C address must be less than 10-bits, got \"0x%x\"", - reg); - + addr); + else if (!(reg & (1 << 31)) && addr > 0x7f) + FAIL_PROP(c, dti, node, prop, "I2C address must be less than 7-bits, got \"0x%x\"", + addr); } } WARNING(i2c_bus_reg, check_i2c_bus_reg, NULL, ®_format, &i2c_bus_bridge);