From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pf1-x432.google.com ([2607:f8b0:4864:20::432]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1fs8SD-0003Kv-FS for barebox@lists.infradead.org; Tue, 21 Aug 2018 15:20:24 +0000 Received: by mail-pf1-x432.google.com with SMTP id y10-v6so8652618pfn.8 for ; Tue, 21 Aug 2018 08:20:11 -0700 (PDT) From: Aleksander Morgado Date: Tue, 21 Aug 2018 17:19:58 +0200 Message-Id: <20180821152001.5747-2-aleksander@aleksander.es> In-Reply-To: <20180821152001.5747-1-aleksander@aleksander.es> References: <20180821152001.5747-1-aleksander@aleksander.es> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH 1/4] ratp: implement i2c read/write support To: barebox@lists.infradead.org, s.hauer@pengutronix.de Cc: Aleksander Morgado Introduce two new RATP commands that allow running i2c read/write operations, very similar in format to the already existing md/mw RATP commands. The messages are defined with a fixed 16-bit long register field, but it will only be treated as a 16-bit address if I2C_FLAG_WIDE_ADDRESS is set in the message flags field. If this flag is unset, the start register address is assumed 8-bit long. If the message includes the I2C_FLAG_MASTER_MODE flag, the start register field is ignored and a i2c master send/receive operation is performed. Signed-off-by: Aleksander Morgado --- common/ratp/Makefile | 1 + common/ratp/i2c.c | 281 +++++++++++++++++++++++++++++++++++++++++++ include/ratp_bb.h | 4 + 3 files changed, 286 insertions(+) create mode 100644 common/ratp/i2c.c diff --git a/common/ratp/Makefile b/common/ratp/Makefile index 2c6d674f6..0234b55c1 100644 --- a/common/ratp/Makefile +++ b/common/ratp/Makefile @@ -4,3 +4,4 @@ obj-y += getenv.o obj-y += md.o obj-y += mw.o obj-y += reset.o +obj-y += i2c.o diff --git a/common/ratp/i2c.c b/common/ratp/i2c.c new file mode 100644 index 000000000..b8d055b67 --- /dev/null +++ b/common/ratp/i2c.c @@ -0,0 +1,281 @@ +/* + * Copyright (c) 2011-2018 Sascha Hauer , Pengutronix + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include +#include +#include +#include +#include +#include +#include + +/* NOTE: + * - Fixed-size fields (e.g. integers) are given just after the header. + * - Variable-length fields are stored inside the buffer[] and their position + * within the buffer[] and their size are given as fixed-sized fields after + * the header. + * The message may be extended at any time keeping backwards compatibility, + * as the position of the buffer[] is given by the buffer_offset field. i.e. + * increasing the buffer_offset field we can extend the fixed-sized section + * to add more fields. + */ + +#define I2C_FLAG_WIDE_ADDRESS (1 << 0) +#define I2C_FLAG_MASTER_MODE (1 << 1) + +struct ratp_bb_i2c_read_request { + struct ratp_bb header; + uint16_t buffer_offset; + uint8_t bus; + uint8_t addr; + uint16_t reg; + uint8_t flags; + uint16_t size; + uint8_t buffer[]; +} __attribute__((packed)); + +struct ratp_bb_i2c_read_response { + struct ratp_bb header; + uint16_t buffer_offset; + uint32_t errno; + uint16_t data_size; + uint16_t data_offset; + uint8_t buffer[]; +} __attribute__((packed)); + +struct ratp_bb_i2c_write_request { + struct ratp_bb header; + uint16_t buffer_offset; + uint8_t bus; + uint8_t addr; + uint16_t reg; + uint8_t flags; + uint16_t data_size; + uint16_t data_offset; + uint8_t buffer[]; +} __attribute__((packed)); + +struct ratp_bb_i2c_write_response { + struct ratp_bb header; + uint16_t buffer_offset; + uint32_t errno; + uint16_t written; + uint8_t buffer[]; +} __attribute__((packed)); + +static int ratp_cmd_i2c_read(const struct ratp_bb *req, int req_len, + struct ratp_bb **rsp, int *rsp_len) +{ + struct ratp_bb_i2c_read_request *i2c_read_req = (struct ratp_bb_i2c_read_request *)req; + struct ratp_bb_i2c_read_response *i2c_read_rsp; + struct i2c_adapter *adapter; + struct i2c_client client; + uint16_t buffer_offset; + int i2c_read_rsp_len; + uint16_t reg; + uint16_t size; + uint32_t wide = 0; + int ret = 0; + + /* At least message header should be valid */ + if (req_len < sizeof(*i2c_read_req)) { + printf("ratp i2c read ignored: size mismatch (%d < %zu)\n", + req_len, sizeof (*i2c_read_req)); + ret = -EINVAL; + goto out_rsp; + } + + /* We don't require any buffer here, but just validate buffer position and size */ + buffer_offset = be16_to_cpu(i2c_read_req->buffer_offset); + if (buffer_offset != req_len) { + printf("ratp i2c read ignored: invalid buffer offset (%hu != %d)\n", + buffer_offset, req_len); + ret = -EINVAL; + goto out_rsp; + } + + reg = be16_to_cpu (i2c_read_req->reg); + size = be16_to_cpu (i2c_read_req->size); + if (i2c_read_req->flags & I2C_FLAG_WIDE_ADDRESS) + wide = I2C_ADDR_16_BIT; + +out_rsp: + /* Avoid reading anything on error */ + if (ret != 0) + size = 0; + + i2c_read_rsp_len = sizeof(*i2c_read_rsp) + size; + i2c_read_rsp = xzalloc(i2c_read_rsp_len); + i2c_read_rsp->header.type = cpu_to_be16(BB_RATP_TYPE_I2C_READ_RETURN); + i2c_read_rsp->buffer_offset = cpu_to_be16(sizeof(*i2c_read_rsp)); + i2c_read_rsp->data_offset = 0; + + /* Don't read anything on error or if 0 bytes were requested */ + if (size > 0) { + adapter = i2c_get_adapter(i2c_read_req->bus); + if (!adapter) { + printf("ratp i2c read ignored: i2c bus %u not found\n", i2c_read_req->bus); + ret = -ENODEV; + goto out; + } + + client.adapter = adapter; + client.addr = i2c_read_req->addr; + + if (i2c_read_req->flags & I2C_FLAG_MASTER_MODE) { + ret = i2c_master_recv(&client, i2c_read_rsp->buffer, size); + } else { + ret = i2c_read_reg(&client, reg | wide, i2c_read_rsp->buffer, size); + } + if (ret != size) { + printf("ratp i2c read ignored: not all bytes read (%u < %u)\n", ret, size); + ret = -EIO; + goto out; + } + ret = 0; + } + +out: + if (ret != 0) { + i2c_read_rsp->data_size = 0; + i2c_read_rsp->errno = cpu_to_be32(ret); + i2c_read_rsp_len = sizeof(*i2c_read_rsp); + } else { + i2c_read_rsp->data_size = cpu_to_be16(size); + i2c_read_rsp->errno = 0; + } + + *rsp = (struct ratp_bb *)i2c_read_rsp; + *rsp_len = i2c_read_rsp_len; + + return ret; +} + +BAREBOX_RATP_CMD_START(I2C_READ) + .request_id = BB_RATP_TYPE_I2C_READ, + .response_id = BB_RATP_TYPE_I2C_READ_RETURN, + .cmd = ratp_cmd_i2c_read +BAREBOX_RATP_CMD_END + + +static int ratp_cmd_i2c_write(const struct ratp_bb *req, int req_len, + struct ratp_bb **rsp, int *rsp_len) +{ + struct ratp_bb_i2c_write_request *i2c_write_req = (struct ratp_bb_i2c_write_request *)req; + struct ratp_bb_i2c_write_response *i2c_write_rsp; + struct i2c_adapter *adapter; + struct i2c_client client; + uint8_t *buffer; + uint16_t buffer_offset; + uint16_t buffer_size; + uint16_t reg; + uint16_t data_offset; + uint16_t data_size; + uint32_t wide = 0; + int ret = 0; + int written = 0; + + /* At least message header should be valid */ + if (req_len < sizeof(*i2c_write_req)) { + printf("ratp i2c write ignored: size mismatch (%d < %zu)\n", + req_len, sizeof (*i2c_write_req)); + ret = -EINVAL; + goto out; + } + + /* Validate buffer position and size */ + buffer_offset = be16_to_cpu(i2c_write_req->buffer_offset); + if (req_len < buffer_offset) { + printf("ratp i2c write ignored: invalid buffer offset (%d < %hu)\n", + req_len, buffer_offset); + ret = -EINVAL; + goto out; + } + buffer_size = req_len - buffer_offset; + buffer = ((uint8_t *)i2c_write_req) + buffer_offset; + + /* Validate data position and size */ + data_offset = be16_to_cpu(i2c_write_req->data_offset); + if (data_offset != 0) { + printf("ratp i2c write ignored: invalid data offset\n"); + ret = -EINVAL; + goto out; + } + data_size = be16_to_cpu(i2c_write_req->data_size); + if (!data_size) { + /* Success */ + goto out; + } + + /* Validate buffer size */ + if (buffer_size < data_size) { + printf("ratp i2c write ignored: size mismatch (%d < %hu): data not fully given\n", + buffer_size, data_size); + ret = -EINVAL; + goto out; + } + + reg = be16_to_cpu (i2c_write_req->reg); + if (i2c_write_req->flags & I2C_FLAG_WIDE_ADDRESS) + wide = I2C_ADDR_16_BIT; + + adapter = i2c_get_adapter(i2c_write_req->bus); + if (!adapter) { + printf("ratp i2c write ignored: i2c bus %u not found\n", i2c_write_req->bus); + ret = -ENODEV; + goto out; + } + + client.adapter = adapter; + client.addr = i2c_write_req->addr; + + if (i2c_write_req->flags & I2C_FLAG_MASTER_MODE) { + written = i2c_master_send(&client, &buffer[data_offset], data_size); + } else { + written = i2c_write_reg(&client, reg | wide, &buffer[data_offset], data_size); + } + + if (written != data_size) { + printf("ratp i2c write ignored: not all bytes written (%u < %u)\n", ret, data_size); + ret = -EIO; + goto out; + } + +out: + i2c_write_rsp = xzalloc(sizeof(*i2c_write_rsp)); + i2c_write_rsp->header.type = cpu_to_be16(BB_RATP_TYPE_I2C_WRITE_RETURN); + i2c_write_rsp->buffer_offset = cpu_to_be16(sizeof(*i2c_write_rsp)); /* n/a */ + + if (ret != 0) { + i2c_write_rsp->written = 0; + i2c_write_rsp->errno = cpu_to_be32(ret); + } else { + i2c_write_rsp->written = cpu_to_be16((uint16_t)written); + i2c_write_rsp->errno = 0; + } + + *rsp = (struct ratp_bb *)i2c_write_rsp; + *rsp_len = sizeof(*i2c_write_rsp); + + return ret; +} + +BAREBOX_RATP_CMD_START(I2C_WRITE) + .request_id = BB_RATP_TYPE_I2C_WRITE, + .response_id = BB_RATP_TYPE_I2C_WRITE_RETURN, + .cmd = ratp_cmd_i2c_write +BAREBOX_RATP_CMD_END diff --git a/include/ratp_bb.h b/include/ratp_bb.h index 3a80cf6ae..32b8040b6 100644 --- a/include/ratp_bb.h +++ b/include/ratp_bb.h @@ -17,6 +17,10 @@ #define BB_RATP_TYPE_MW 12 #define BB_RATP_TYPE_MW_RETURN 13 #define BB_RATP_TYPE_RESET 14 +#define BB_RATP_TYPE_I2C_READ 15 +#define BB_RATP_TYPE_I2C_READ_RETURN 16 +#define BB_RATP_TYPE_I2C_WRITE 17 +#define BB_RATP_TYPE_I2C_WRITE_RETURN 18 struct ratp_bb { uint16_t type; 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