Re: [PATCH v2 1/1] misc: st32boot: Add stm32 upgrade protocol handling

Antonio Borneo
2014-10-13T10:08:27Z

On Fri, Oct 10, 2014 at 7:54 PM, Karol Wrona <k.wrona@samsung.com> wrote:
> Adds stm32 bootloader protocol handling.
>
> SPI transfers are done using DMA safe buffer which is allocated once per
> spi upgrade life cycle. Now it supports only SPI bus but it looks that UART
> or I2C are quite similar and it can be used as start platform for implementing
> their handling.
>
> It was tested on STM32F401 MCU.

Hi Karol,

I'm working at a similar driver but for the I2C version of STM32
bootloader. I was thinking to implement and test SPI too before
publishing the whole.
My plan is for a more generic STM32 support, while your driver is
quite specific for device STM32F401.
Anyway, I believe I can adapt my driver on top of your work.

While writing the kernel driver for I2C, I have enhanced the userspace
tool stm32flash [1] (originally for UART only) to supports I2C.
With stm32flash it's easy to verify the protocol of STM32 bootloader
before working in kernel space.
I would extend it to SPI while working at SPI driver.

[1] https://code.google.com/p/stm32flash/

With this review I'm not going deeply in the SPI version of STM32
bootloader (I'm still studying it).
Also, I cannot easily run the code in this patch; I miss the proper HW
and this patch cannot run stand-alone since intended as "library" for
your sensor hub driver.

>
> Change-Id: I5e5b441310c897ff822e65041531d80ea0e7426c
> Signed-off-by: Karol Wrona <k.wrona@samsung.com>
> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
> ---
> drivers/misc/Kconfig | 1 +
> drivers/misc/Makefile | 1 +
> drivers/misc/stm32boot/Kconfig | 6 +
> drivers/misc/stm32boot/Makefile | 3 +
> drivers/misc/stm32boot/stm32_core.c | 412 +++++++++++++++++++++++++++++++++++
> drivers/misc/stm32boot/stm32_core.h | 81 +++++++
> drivers/misc/stm32boot/stm32_spi.c | 108 +++++++++
> include/linux/stm32fwu.h | 47 ++++

Only personal preference but, instead of "stm32boot", what about
"stm32bootloader" or "stm32fwu" ?

> 8 files changed, 659 insertions(+)
> create mode 100644 drivers/misc/stm32boot/Kconfig
> create mode 100644 drivers/misc/stm32boot/Makefile
> create mode 100644 drivers/misc/stm32boot/stm32_core.c
> create mode 100644 drivers/misc/stm32boot/stm32_core.h
> create mode 100644 drivers/misc/stm32boot/stm32_spi.c
> create mode 100644 include/linux/stm32fwu.h
>
> diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
> index bbeb451..1eaed30 100644
> --- a/drivers/misc/Kconfig
> +++ b/drivers/misc/Kconfig
> @@ -528,4 +528,5 @@ source "drivers/misc/mic/Kconfig"
> source "drivers/misc/genwqe/Kconfig"
> source "drivers/misc/echo/Kconfig"
> source "drivers/misc/cxl/Kconfig"
> +source "drivers/misc/stm32boot/Kconfig"
> endmenu
> diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
> index 7d5c4cd..80d1524 100644
> --- a/drivers/misc/Makefile
> +++ b/drivers/misc/Makefile
> @@ -56,3 +56,4 @@ obj-$(CONFIG_GENWQE) += genwqe/
> obj-$(CONFIG_ECHO) += echo/
> obj-$(CONFIG_VEXPRESS_SYSCFG) += vexpress-syscfg.o
> obj-$(CONFIG_CXL_BASE) += cxl/
> +obj-$(CONFIG_STM32_UPGRADE_PROTOCOL) += stm32boot/
> diff --git a/drivers/misc/stm32boot/Kconfig b/drivers/misc/stm32boot/Kconfig
> new file mode 100644
> index 0000000..1484441
> --- /dev/null
> +++ b/drivers/misc/stm32boot/Kconfig
> @@ -0,0 +1,6 @@
> +config STM32_UPGRADE_PROTOCOL
> + tristate "STM32 upgrade protocol support"
> + depends on SPI
> + help
> + STM32 microcontroller bootloader upgrade protocol.
> + Say Y if you want to use it.
> diff --git a/drivers/misc/stm32boot/Makefile b/drivers/misc/stm32boot/Makefile
> new file mode 100644
> index 0000000..9d5935b
> --- /dev/null
> +++ b/drivers/misc/stm32boot/Makefile
> @@ -0,0 +1,3 @@
> +#EXTRA_CFLAGS+= -O0
> +
> +obj-$(CONFIG_STM32_UPGRADE_PROTOCOL) += stm32_core.o stm32_spi.o
> diff --git a/drivers/misc/stm32boot/stm32_core.c b/drivers/misc/stm32boot/stm32_core.c
> new file mode 100644
> index 0000000..bd68598
> --- /dev/null
> +++ b/drivers/misc/stm32boot/stm32_core.c
> @@ -0,0 +1,412 @@
> +/*
> + * Copyright (C) 2014, Samsung Electronics Co. Ltd. All Rights Reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * 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.
> + *

You can remove line above

> + */
> +
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +#include <linux/stm32fwu.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>

Include files in alphabetic order

> +#include "stm32_core.h"
> +
> +static inline int stm32fwu_wait_for_ack(struct stm32fwu_fw *fw, int retries)
> +{
> + return fw->wait_for_ack(fw, retries);
> +}
> +
> +static inline int stm32fwu_send_cmd(struct stm32fwu_fw *fw,
> + struct stm32fwu_cmd *cmd)
> +{
> + return fw->send_cmd(fw, cmd);
> +}
> +
> +static inline int stm32fwu_write(struct stm32fwu_fw *fw, const u8 *buf, int len)
> +{
> + return fw->write(fw, buf, len);
> +}
> +
> +static inline int stm32fwu_read(struct stm32fwu_fw *fw, u8 *buf, int len)
> +{
> + return fw->read(fw, buf, len);
> +}
> +
> +static int send_addr(struct stm32fwu_fw *fw, u32 addr)
> +{
> + int ret;
> + u8 *buffer = fw->buffer;
> +
> + buffer[0] = (addr >> 24) & 0xFF;
> + buffer[1] = (addr >> 16) & 0xFF;
> + buffer[2] = (addr >> 8) & 0xFF;
> + buffer[3] = addr & 0xFF;
> + buffer[4] = buffer[0] ^ buffer[1] ^ buffer[2] ^ buffer[3];
> +
> + ret = stm32fwu_write(fw, buffer, STM32FWU_ADDR_LEN);
> + if (ret < 0)
> + return ret;
> +
> + return stm32fwu_wait_for_ack(fw, STM32FWU_COMMON_COUNT);
> +}
> +
> +static int fwu_write(struct stm32fwu_fw *fw, u32 addr, const u8 *buffer,
> + int len)
> +{
> + int ret, i;
> + u8 *sbuf = fw->buffer;
> + u8 xor = 0;
> + struct stm32fwu_cmd cmd = {
> + .cmd = STM32FWU_WRITE_MEM_CMD,
> + .neg_cmd = ~STM32FWU_WRITE_MEM_CMD,

Every command requires this "neg_cmd = ~cmd".
You can move this operation inside stm32fwu_spi_send_cmd() and remove
the field neg_cmd.

Then, you can directly pass as function parameter cmd and timeout. No
need to build the struct for just two values.

> + .timeout = STM32FWU_CMD_COUNT,
> + };
> +
> + if (len > STM32FWU_MAX_TRANSFER_SIZE) {
> + dev_err(fw->dev, "More than 256 bytes per transfer\n");
> + return -EINVAL;
> + }
> +
> + ret = stm32fwu_send_cmd(fw, &cmd);
> + if (ret < 0)
> + return ret;
> +
> + ret = send_addr(fw, addr);
> + if (ret < 0)
> + return ret;
> +
> + /* the same buffer is used for commands and data so the order really
> + * matters here */
> + memcpy(&sbuf[1], buffer, len);
> +
> + /* just in case - check if smaller chunks are 16-bit aligned */

Interesting!
The ST application note AN2606 about bootloader in general reports
that all "write operations using bootloader must only be Word-aligned
(the address should be multiple of 4). The number of data to be
written must also be a multiple of 4 bytes".
Anyhow, I checked the specific AN4268 for SPI version, and it mentions
16 bits alignment and data multiple of two bytes.

I will cross check with ST.
Did you tried to write in chunks of 2 bytes?

> + if (len < STM32FWU_MAX_TRANSFER_SIZE) {

Remove extra space between "len" and "<".
Also the {} can be removed.

> + if (len & 0x1)
> + sbuf[++len] = 0xFF;
> + }

For application note, extending the data in sbuf with one byte 0xFF is
mandatory if len is not multiple of two.
Since you need to guarantee the buffer is long enough, the check
"len<STM32FWU_MAX_TRANSFER_SIZE" could be skipped.

> +
> + sbuf[0] = len - 1;
> +
> + /* compute checksum */
> + for (i = 0; i < len + 1; ++i)
> + xor ^= sbuf[i];
> + sbuf[len + 1] = xor;
> +
> + /* NOTE AN4286
> + * in some conditions the master has to wait 1 ms here */
> + usleep_range(1000, 1100);
> +
> + ret = stm32fwu_write(fw, sbuf, len + 2);
> + if (ret < 0)
> + return ret;
> +
> + return stm32fwu_wait_for_ack(fw, STM32FWU_COMMON_COUNT);
> +}
> +
> +static int fwu_erase(struct stm32fwu_fw *fw)
> +{
> + int ret;
> + u8 *sbuf = fw->buffer;
> + struct stm32fwu_cmd cmd = {
> + .cmd = STM32FWU_ERASE_CMD,
> + .neg_cmd = ~STM32FWU_ERASE_CMD,

ditto

> + .timeout = STM32FWU_CMD_COUNT,
> + };
> +
> + ret = stm32fwu_send_cmd(fw, &cmd);
> + if (ret < 0)
> + return ret;
> +
> + /* global erase */
> + sbuf[0] = 0xFF;
> + sbuf[1] = 0xFF;
> + sbuf[2] = 0x00;
> +
> + ret = stm32fwu_write(fw, sbuf, STM32FWU_ERASE_CMD_LEN);
> + if (ret < 0)
> + return ret;
> +
> + return stm32fwu_wait_for_ack(fw, STM32FWU_ERASE_COUNT);

See my comments below about the macro STM32FWU_ERASE_COUNT

> +}
> +
> +/**
> + * stm32fwu_get() - gets bootloader information frame
> + * @fw: fw object.
> + *
> + * Read bootloader information:
> + *
> + * Byte 1 bootloader version (0 < version < 255), example: 0x10 = version 1.0.
> + *
> + * Byte 2 0x00 (Get command)
> + *
> + * Byte 3 0x01 (Get Version)
> + *
> + * Byte 4 0x02 (Get ID)
> + *
> + * Byte 5 0x11 (Read Memory command)
> + *
> + * Byte 6 0x21 (Go command)
> + *
> + * Byte 7 0x31 (Write Memory command)
> + *
> + * Byte 8 0x44 (Erase command)
> + *
> + * Byte 9 0x63 (Write Protect command)
> + *
> + * Byte 10 0x73 (Write Unprotect command)
> + *
> + * Byte 11 0x82 (Readout Protect command)
> + *
> + * Byte 12 0x92 (Readout Unprotect command)

In general case, we should read at run-time from bootloader the list
of supported commands and use only what is supported; not all versions
of STM32 bootloader use the commands you hardcoded in this driver.
But it's clear that you are focusing at the STM32F401 chip on your
system; I cannot ask you to implement what you cannot test. Further
patches should extend the picture.

> + *
> + * Return: read byte count or error code.
> + */
> +int stm32fwu_get(struct stm32fwu_fw *fw)
> +{
> + int ret, count = 0;
> +
> + struct stm32fwu_cmd cmd = {
> + .cmd = STM32FWU_GET_CMD,
> + .neg_cmd = ~STM32FWU_GET_CMD,

ditto

> + .timeout = STM32FWU_CMD_COUNT,
> + };
> +
> + ret = stm32fwu_send_cmd(fw, &cmd);
> + if (ret < 0)
> + return ret;
> +
> + ret = stm32fwu_read(fw, &fw->buffer[STM32FWU_MAX_BUFFER_SIZE], 1);
> + if (ret < 0)
> + return ret;
> +
> + count = fw->buffer[STM32FWU_MAX_BUFFER_SIZE];
> + if (count >= STM32FWU_MAX_TRANSFER_SIZE)
> + return -EINVAL;
> +
> + ret = stm32fwu_read(fw, &fw->buffer[STM32FWU_MAX_BUFFER_SIZE], count);
> + if (ret < 0)
> + return ret;
> +
> + ret = stm32fwu_wait_for_ack(fw, STM32FWU_COMMON_COUNT);
> + if (ret < 0)
> + return ret;
> +
> + return count;
> +}
> +EXPORT_SYMBOL(stm32fwu_get);
> +
> +/**
> + * stm32fwu_get() - gets bootloader information frame
> + * @fw: fw object.
> + *
> + * Return: < 0 - error code, any positive value means success.
> + */
> +int stm32fwu_get_version(struct stm32fwu_fw *fw)
> +{
> + int ret;
> +
> + struct stm32fwu_cmd cmd = {
> + .cmd = STM32FWU_GET_VERSION_CMD,
> + .neg_cmd = ~STM32FWU_GET_VERSION_CMD,

ditto

> + .timeout = STM32FWU_CMD_COUNT,
> + };
> +
> + ret = stm32fwu_send_cmd(fw, &cmd);
> + if (ret < 0)
> + return ret;
> +
> + ret = stm32fwu_read(fw, &fw->buffer[STM32FWU_MAX_BUFFER_SIZE], 1);
> + if (ret < 0)
> + return ret;
> +
> + ret = stm32fwu_wait_for_ack(fw, STM32FWU_COMMON_COUNT);
> + if (ret < 0)
> + return ret;
> +
> + return fw->buffer[STM32FWU_MAX_BUFFER_SIZE];
> +}
> +EXPORT_SYMBOL(stm32fwu_get_version);
> +
> +/**
> + * stm32fwu_send_sync() - sends bootloader synchronization frame
> + * @fw: fw object.
> + *
> + * It is used during SPI upgrade.
> + *
> + * Return: if succeed the number of ack waiting cycles or error code.
> + */
> +int stm32fwu_send_sync(struct stm32fwu_fw *fw)
> +{
> + int ret;
> +
> + dev_info(fw->dev, "send sync byte for upgrade\n");
> +
> + fw->buffer[0] = STM32FWU_SPI_SOF;
> +
> + ret = stm32fwu_write(fw, fw->buffer, 1);
> + if (ret < 0)
> + return ret;
> +
> + return stm32fwu_wait_for_ack(fw, STM32FWU_CMD_COUNT);

Remove extra space after "return"

> +}
> +EXPORT_SYMBOL(stm32fwu_send_sync);
> +
> +/**
> + * stm32fwu_update() - runs all firmware update work
> + * @fw: fw object.
> + *
> + * Return: status code < 0 if error.
> + */
> +int stm32fwu_update(struct stm32fwu_fw *fw)
> +{
> + int ret = 0, remaining;
> + u32 pos = 0;
> + u32 fw_addr = STM32FWU_APP_ADDR;
> + int block = STM32FWU_MAX_TRANSFER_SIZE;
> + int count = 0, err_count = 0, retry_count = 0;
> +
> + struct stm32fwu_cmd cmd = {
> + .cmd = STM32FWU_GO_ADDR_CMD,
> + .neg_cmd = ~STM32FWU_GO_ADDR_CMD,

ditto

> + .timeout = 1000,

Why you need such long timeout here?
If no reason, then keep it coherent with the rest of the code and put
.timeout = STM32FWU_CMD_COUNT,

> + };
> +
> + dev_info(fw->dev, "%s start\n", __func__);
> +
> + ret = fwu_erase(fw);
> + if (ret < 0) {
> + dev_err(fw->dev, "%s, fw_erase_stm failed %d\n", __func__, ret);
> + return ret;
> + }
> +
> + remaining = fw->fw_len;
> +
> + while (remaining > 0) {
> + if (block > remaining)
> + block = remaining;
> +
> + while (retry_count < 3) {
> + ret = fwu_write(fw, fw_addr, fw->fw_data + pos, block);
> + if (ret < 0) {
> + dev_err(fw->dev,
> + "Returned %d writing to addr 0x%08X\n",
> + ret, fw_addr);
> + retry_count++;
> + err_count++;
> + continue;
> + }
> + retry_count = 0;
> + break;
> + }
> +
> + if (ret < 0) {

Extra space after "ret"

> + dev_err(fw->dev,
> + "Writing MEM failed: %d, retry cont: %d\n",
> + ret, err_count);
> + return ret;
> + }
> +
> + remaining -= block;
> + pos += block;
> + fw_addr += block;
> + if (count++ == 20) {
> + dev_info(fw->dev, "Updated %u bytes / %u bytes\n",
> + pos, fw->fw_len);
> + count = 0;
> + }
> + }
> +
> + dev_info(fw->dev,
> + "Firmware download success.(%d bytes, retry %d)\n", pos,
> + err_count);
> +
> + /* STM : GO USER ADDR */
> + ret = stm32fwu_send_cmd(fw, &cmd);
> + if (ret < 0)
> + return ret;
> +
> + return send_addr(fw, STM32FWU_APP_ADDR);

Extra space after ","

> +}
> +EXPORT_SYMBOL(stm32fwu_update);
> +
> +/**
> + * stm32fwu_init() - creates firmware upgrade instance
> + * @dev: Pointer to device.
> + * @iface: Interface type.
> + * @data: Pointer to firmware data.
> + * @len: Length of firmware data in bytes.
> + *
> + * It allocates the place for fwu structure and transfer buffer so it should be
> + * deinitialized by stm32fw_destroy(). Firmware upgrade is simple operation
> + * and it was assumed that it will be called form one context so there is no
> + * locking for fwu functions.
> + *
> + * Return: Pointer to firmware upgrade structure.
> + */
> +struct stm32fwu_fw *stm32fwu_init(struct device *dev,
> + enum stm32fwu_iface iface, const u8 *data,
> + int len)
> +{
> + struct stm32fwu_fw *fw;
> +
> + if (iface >= STM32_MAX || iface < 0) {
> + dev_err(dev, "wrong iface type\n");
> + return NULL;
> + }
> +
> + fw = devm_kzalloc(dev, sizeof(*fw), GFP_KERNEL);

This buffer and next one below are allocated with devm_kzalloc() but
later on in this function you free them with kfree() and in next
function with devm_kfree().
Please double check.

> + if (fw == NULL)
> + return NULL;
> +
> + /* 2 times for tx and rx buffer */
> + fw->buffer = devm_kzalloc(dev, 2 * STM32FWU_MAX_BUFFER_SIZE,
> + GFP_KERNEL | GFP_DMA);
> + if (fw->buffer == NULL) {
> + kfree(fw);
> + return NULL;
> + }
> +
> + fw->dev = dev;
> + fw->fw_len = len;
> + fw->fw_data = data;
> +
> + switch (iface) {
> + case STM32_SPI:
> + stm32fwu_spi_init(fw);
> + break;
> + default:
> + pr_err("wrong interface\n");
> + goto _err;
> + }
> +
> + return fw;
> +_err:
> + kfree(fw->buffer);
> + kfree(fw);
> + return NULL;
> +}
> +EXPORT_SYMBOL(stm32fwu_init);
> +
> +/**
> + * stm32fwu_destroy() - cleans up fwu structure and buffer.
> + * @fw: Pointer to fwu structure.
> + */
> +void stm32fwu_destroy(struct stm32fwu_fw *fw)
> +{
> + devm_kfree(fw->dev, fw->buffer);
> + devm_kfree(fw->dev, fw);
> +}
> +EXPORT_SYMBOL(stm32fwu_destroy);
> +
> +MODULE_AUTHOR("Karol Wrona <k.wrona@samsung.com>");
> +MODULE_DESCRIPTION("STM32 upgrade protocol");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/misc/stm32boot/stm32_core.h b/drivers/misc/stm32boot/stm32_core.h
> new file mode 100644
> index 0000000..8d89a6d
> --- /dev/null
> +++ b/drivers/misc/stm32boot/stm32_core.h
> @@ -0,0 +1,81 @@
> +/*
> + * Copyright (C) 2014, Samsung Electronics Co. Ltd. All Rights Reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * 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.
> + *

Remove line above

> + */
> +
> +#ifndef _STM32_CORE_H_
> +#define _STM32_CORE_H_
> +
> +#define STM32FWU_ADDR_LEN 5
> +#define STM32FWU_ERASE_CMD_LEN 3
> +
> +/* Protocol */
> +#define STM32FWU_SPI_SOF 0x5A
> +#define STM32FWU_ACK 0x79
> +#define STM32FWU_ACK2 0xF9
> +#define STM32FWU_NACK 0x1F
> +
> +#define STM32FWU_MAX_TRANSFER_SIZE 256
> +#define STM32FWU_MAX_BUFFER_SIZE 260
> +
> +#define STM32FWU_APP_ADDR 0x08000000
> +
> +/* Retries counts */
> +#define STM32FWU_ERASE_COUNT 7000

Hummm, not enough! This value means 7.0 ~ 7.7 seconds.
There are two flash size for STM32F401 (the model you support in this driver).
Datasheets [3] and [4] report the worst case delay for mass erase. It
is 8 seconds for 256K of flash, 16 seconds for 512K of flash.

[3] http://www.st.com/web/en/resource/technical/document/datasheet/DM00086815.pdf
[4] http://www.st.com/web/en/resource/technical/document/datasheet/DM00102166.pdf

Other STM32 devices requires even longer delay.
At least correct it with the right value for your device.

In my driver I'm considering to replace mass erase with a loop on
sector erase. It would requires more code in kernel, but uses shorter
timeout for each operation. At least I can track what's happening
halfway.

> +#define STM32FWU_CMD_COUNT 30
> +#define STM32FWU_COMMON_COUNT 20
> +
> +/* Commands */
> +#define STM32FWU_WRITE_MEM_CMD 0x31
> +#define STM32FWU_GO_ADDR_CMD 0x21
> +#define STM32FWU_ERASE_CMD 0x44
> +#define STM32FWU_GET_CMD 0x00
> +#define STM32FWU_GET_VERSION_CMD 0x01
> +
> +/**
> + * struct stm32fwu_cmd - Upgrade command
> + * @cmd: Fwu command.
> + * @neg_cmd: Bit negation of Fwu command used xor'ed in STM.
> + * @timeout: Number of retries.
> + */
> +struct stm32fwu_cmd {
> + u8 cmd;
> + u8 neg_cmd;
> + int timeout;
> +};
> +
> +/**
> + * struct stm32fwu_fw - Generic representation for STM32 fw upgrade
> + * @dev: Pointer to device.
> + * @wait_for_ack: ACK callback.
> + * @send_cmd: Command callback.
> + * @write: Write callback.
> + * @read: Read callback.
> + * @fw_data: Pointer to firmware binary.
> + * @fw_len: The length of fw bin.
> + * @buffer: Pointer to SPI buffer: should be DMA safe
> + */
> +struct stm32fwu_fw {
> + int (*wait_for_ack)(struct stm32fwu_fw *fw, int retries);
> + int (*send_cmd)(struct stm32fwu_fw *fw, struct stm32fwu_cmd *cmd);
> + int (*write)(struct stm32fwu_fw *fw, const u8 *buf, int len);
> + int (*read)(struct stm32fwu_fw *fw, u8 *buf, int len);
> + const u8 *fw_data;
> + int fw_len;
> + u8 *buffer;
> + struct device *dev;
> +};
> +
> +void stm32fwu_spi_init(struct stm32fwu_fw *fw);
> +
> +#endif /*_STM32_CORE_H_ */
> diff --git a/drivers/misc/stm32boot/stm32_spi.c b/drivers/misc/stm32boot/stm32_spi.c
> new file mode 100644
> index 0000000..ee9f39e
> --- /dev/null
> +++ b/drivers/misc/stm32boot/stm32_spi.c
> @@ -0,0 +1,108 @@
> +/*
> + * Copyright (C) 2014, Samsung Electronics Co. Ltd. All Rights Reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * 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.
> + *

Remove line above

> + */
> +
> +#include <linux/module.h>
> +#include <linux/stm32fwu.h>
> +#include <linux/spi/spi.h>
> +#include <linux/delay.h>

Includes in alphabetic order

> +#include "stm32_core.h"
> +
> +static int stm32fwu_spi_write(struct stm32fwu_fw *fw, const u8 *buf, int len)
> +{
> + struct spi_device *sdev = to_spi_device(fw->dev);
> +
> + struct spi_message m;
> + struct spi_transfer t = {
> + .len = len,
> + .tx_buf = buf,
> + .bits_per_word = 8,
> + };
> +
> + spi_message_init(&m);
> + spi_message_add_tail(&t, &m);
> + return spi_sync(sdev, &m);
> +}
> +
> +static int stm32fwu_spi_read(struct stm32fwu_fw *fw, u8 *buf, int len)
> +{
> + struct spi_device *sdev = to_spi_device(fw->dev);
> +
> + struct spi_message m;
> + struct spi_transfer t = {
> + .len = len,
> + .rx_buf = buf,
> + .bits_per_word = 8,
> + };
> +
> + spi_message_init(&m);
> + spi_message_add_tail(&t, &m);
> + return spi_sync(sdev, &m);
> +}
> +
> +static int stm32fwu_spi_wait_for_ack(struct stm32fwu_fw *fw, int retires)
> +{
> + int ret, i = 0;
> + u8 *buf = &fw->buffer[STM32FWU_MAX_BUFFER_SIZE];
> +
> + while (i < retires) {
> + ret = stm32fwu_spi_read(fw, buf, 1);
> + if (ret < 0) {
> + dev_err(fw->dev,
> + "firmware upgread wait for ack fail\n");

s/upgread/upgrade/

> + return ret;
> + }
> +
> + if (fw->buffer[STM32FWU_MAX_BUFFER_SIZE] == STM32FWU_ACK ||
> + fw->buffer[STM32FWU_MAX_BUFFER_SIZE] == STM32FWU_ACK2) {
> + return i;
> + }
> +
> + if (fw->buffer[STM32FWU_MAX_BUFFER_SIZE] == STM32FWU_NACK)
> + return -EPROTO;
> +
> + usleep_range(1000, 1100);
> + i++;
> + }
> +
> + dev_err(fw->dev, "fw ack timeout\n");
> +
> + return -ETIMEDOUT;
> +}
> +
> +static int stm32fwu_spi_send_cmd(struct stm32fwu_fw *fw,
> + struct stm32fwu_cmd *cmd)
> +{
> + int ret;
> +
> + fw->buffer[0] = STM32FWU_SPI_SOF;
> + fw->buffer[1] = cmd->cmd;
> + fw->buffer[2] = cmd->neg_cmd;
> +
> + ret = stm32fwu_spi_write(fw, fw->buffer, 3);
> + if (ret < 0) {
> + dev_err(fw->dev, "fw cmd write fail\n");
> + return ret;
> + }
> +
> + return stm32fwu_spi_wait_for_ack(fw, cmd->timeout);
> +}
> +
> +void stm32fwu_spi_init(struct stm32fwu_fw *fw)
> +{
> + fw->write = stm32fwu_spi_write;
> + fw->read = stm32fwu_spi_read;
> + fw->wait_for_ack = stm32fwu_spi_wait_for_ack;
> + fw->send_cmd = stm32fwu_spi_send_cmd;
> +}
> diff --git a/include/linux/stm32fwu.h b/include/linux/stm32fwu.h
> new file mode 100644
> index 0000000..aa830d6
> --- /dev/null
> +++ b/include/linux/stm32fwu.h
> @@ -0,0 +1,47 @@
> +/*
> + * Copyright (C) 2014, Samsung Electronics Co. Ltd. All Rights Reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * 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.
> + *

Remove line above

Best Regards,
Antonio

> + */
> +
> +#ifndef _STM32FWU_H_
> +#define _STM32FWU_H_
> +
> +/**
> + * enum stm32fwu_iface - upgrade interfaces for STM32 MCU's
> + * @STM32_SPI: SPI interface.
> + * @STM32_MAX: terminator.
> + */
> +enum stm32fwu_iface {
> + STM32_SPI,
> + /* Generally for future use, i.e. UART upgrade algorithm looks pretty
> + * similar. */
> + STM32_MAX
> +};
> +
> +struct stm32fwu_fw;
> +
> +struct stm32fwu_fw *stm32fwu_init(struct device *dev,
> + enum stm32fwu_iface iface, const u8 *data,
> + int len);
> +
> +void stm32fwu_destroy(struct stm32fwu_fw *fw);
> +
> +int stm32fwu_send_sync(struct stm32fwu_fw *fw);
> +
> +int stm32fwu_update(struct stm32fwu_fw *fw);
> +
> +int stm32fwu_get(struct stm32fwu_fw *fw);
> +
> +int stm32fwu_get_version(struct stm32fwu_fw *fw);
> +
> +#endif /* _STM32FWU_H_ */
> --
> 1.7.9.5
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html