new file mode 100644
@@ -0,0 +1,15 @@
+What: /sys/bus/spi/<dev>/update_firmware
+Date: Jul 2021
+Contact: sebastian.reichel@collabora.com
+Description: Write 1 to this file to update the ACHC microcontroller
+ firmware via the EzPort interface. For this the kernel
+ will load "achc.bin" via the firmware API (so usually
+ from /lib/firmware). The write will block until the FW
+ has either been flashed successfully or an error occured.
+
+What: /sys/bus/spi/<dev>/reset
+Date: Jul 2021
+Contact: sebastian.reichel@collabora.com
+Description: This file represents the microcontroller's reset line.
+ 1 means the reset line is asserted, 0 means it's not
+ asserted. The file is read and writable.
@@ -208,6 +208,18 @@ config CS5535_CLOCK_EVENT_SRC
MFGPTs have a better resolution and max interval than the
generic PIT, and are suitable for use as high-res timers.
+config GEHC_ACHC
+ tristate "GEHC ACHC support"
+ depends on SPI && SYSFS
+ depends on SOC_IMX53 || COMPILE_TEST
+ select FW_LOADER
+ help
+ Support for GE ACHC microcontroller, that is part of the GE
+ PPD device.
+
+ To compile this driver as a module, choose M here: the
+ module will be called gehc-achc.
+
config HP_ILO
tristate "Channel interface driver for the HP iLO processor"
depends on PCI
@@ -24,6 +24,7 @@ obj-$(CONFIG_KGDB_TESTS) += kgdbts.o
obj-$(CONFIG_SGI_XP) += sgi-xp/
obj-$(CONFIG_SGI_GRU) += sgi-gru/
obj-$(CONFIG_CS5535_MFGPT) += cs5535-mfgpt.o
+obj-$(CONFIG_GEHC_ACHC) += gehc-achc.o
obj-$(CONFIG_HP_ILO) += hpilo.o
obj-$(CONFIG_APDS9802ALS) += apds9802als.o
obj-$(CONFIG_ISL29003) += isl29003.o
new file mode 100644
@@ -0,0 +1,565 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * datasheet: https://www.nxp.com/docs/en/data-sheet/K20P144M120SF3.pdf
+ *
+ * Copyright (C) 2018-2021 Collabora
+ * Copyright (C) 2018-2021 GE Healthcare
+ */
+
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/gpio/consumer.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/spi/spi.h>
+
+#define ACHC_MAX_FREQ_HZ 300000
+#define ACHC_FAST_READ_FREQ_HZ 1000000
+
+struct achc_data {
+ struct spi_device *main;
+ struct spi_device *ezport;
+ struct gpio_desc *reset;
+
+ struct mutex device_lock; /* avoid concurrent device access */
+};
+
+#define EZPORT_RESET_DELAY_MS 100
+#define EZPORT_STARTUP_DELAY_MS 200
+#define EZPORT_WRITE_WAIT_MS 10
+#define EZPORT_TRANSFER_SIZE 2048
+
+#define EZPORT_CMD_SP 0x02 /* flash section program */
+#define EZPORT_CMD_RDSR 0x05 /* read status register */
+#define EZPORT_CMD_WREN 0x06 /* write enable */
+#define EZPORT_CMD_FAST_READ 0x0b /* flash read data at high speed */
+#define EZPORT_CMD_RESET 0xb9 /* reset chip */
+#define EZPORT_CMD_BE 0xc7 /* bulk erase */
+#define EZPORT_CMD_SE 0xd8 /* sector erase */
+
+#define EZPORT_SECTOR_SIZE 4096
+#define EZPORT_SECTOR_MASK (EZPORT_SECTOR_SIZE - 1)
+
+#define EZPORT_STATUS_WIP BIT(0) /* write in progress */
+#define EZPORT_STATUS_WEN BIT(1) /* write enable */
+#define EZPORT_STATUS_BEDIS BIT(2) /* bulk erase disable */
+#define EZPORT_STATUS_FLEXRAM BIT(3) /* FlexRAM mode */
+#define EZPORT_STATUS_WEF BIT(6) /* write error flag */
+#define EZPORT_STATUS_FS BIT(7) /* flash security */
+
+static void ezport_reset(struct gpio_desc *reset)
+{
+ gpiod_set_value(reset, 1);
+ msleep(EZPORT_RESET_DELAY_MS);
+ gpiod_set_value(reset, 0);
+ msleep(EZPORT_STARTUP_DELAY_MS);
+}
+
+static int ezport_start_programming(struct spi_device *spi, struct gpio_desc *reset)
+{
+ struct spi_message msg;
+ struct spi_transfer assert_cs = {
+ .cs_change = 1,
+ };
+ struct spi_transfer release_cs = { };
+ int ret;
+
+ spi_bus_lock(spi->master);
+
+ /* assert chip select */
+ spi_message_init(&msg);
+ spi_message_add_tail(&assert_cs, &msg);
+ ret = spi_sync_locked(spi, &msg);
+ if (ret)
+ goto fail;
+
+ msleep(EZPORT_STARTUP_DELAY_MS);
+
+ /* reset with asserted chip select to switch into programming mode */
+ ezport_reset(reset);
+
+ /* release chip select */
+ spi_message_init(&msg);
+ spi_message_add_tail(&release_cs, &msg);
+ ret = spi_sync_locked(spi, &msg);
+
+fail:
+ spi_bus_unlock(spi->master);
+ return ret;
+}
+
+static void ezport_stop_programming(struct spi_device *spi, struct gpio_desc *reset)
+{
+ /* reset without asserted chip select to return into normal mode */
+ spi_bus_lock(spi->master);
+ ezport_reset(reset);
+ spi_bus_unlock(spi->master);
+}
+
+static int ezport_get_status_register(struct spi_device *spi)
+{
+ int ret;
+
+ ret = spi_w8r8(spi, EZPORT_CMD_RDSR);
+ if (ret < 0)
+ return ret;
+ if (ret == 0xff) {
+ dev_err(&spi->dev, "Invalid EzPort status, EzPort is not functional!\n");
+ return -EINVAL;
+ }
+
+ return ret;
+}
+
+static int ezport_soft_reset(struct spi_device *spi)
+{
+ u8 cmd = EZPORT_CMD_RESET;
+ int ret;
+
+ ret = spi_write(spi, &cmd, 1);
+ if (ret < 0)
+ return ret;
+
+ msleep(EZPORT_STARTUP_DELAY_MS);
+
+ return 0;
+}
+
+static int ezport_send_simple(struct spi_device *spi, u8 cmd)
+{
+ int ret;
+
+ ret = spi_write(spi, &cmd, 1);
+ if (ret < 0)
+ return ret;
+
+ return ezport_get_status_register(spi);
+}
+
+static int ezport_wait_write(struct spi_device *spi, u32 retries)
+{
+ int ret;
+ u32 i;
+
+ for (i = 0; i < retries; i++) {
+ ret = ezport_get_status_register(spi);
+ if (ret >= 0 && !(ret & EZPORT_STATUS_WIP))
+ break;
+ msleep(EZPORT_WRITE_WAIT_MS);
+ }
+
+ return ret;
+}
+
+static int ezport_write_enable(struct spi_device *spi)
+{
+ int ret = 0, retries = 3;
+
+ for (retries = 0; retries < 3; retries++) {
+ ret = ezport_send_simple(spi, EZPORT_CMD_WREN);
+ if (ret > 0 && ret & EZPORT_STATUS_WEN)
+ break;
+ }
+
+ if (!(ret & EZPORT_STATUS_WEN)) {
+ dev_err(&spi->dev, "EzPort write enable timed out\n");
+ return -ETIMEDOUT;
+ }
+ return 0;
+}
+
+static int ezport_bulk_erase(struct spi_device *spi)
+{
+ int ret;
+ static const u8 cmd = EZPORT_CMD_BE;
+
+ dev_dbg(&spi->dev, "EzPort bulk erase...\n");
+
+ ret = ezport_write_enable(spi);
+ if (ret < 0)
+ return ret;
+
+ ret = spi_write(spi, &cmd, 1);
+ if (ret < 0)
+ return ret;
+
+ ret = ezport_wait_write(spi, 1000);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int ezport_section_erase(struct spi_device *spi, u32 address)
+{
+ u8 query[] = {EZPORT_CMD_SE, (address >> 16) & 0xff, (address >> 8) & 0xff, address & 0xff};
+ int ret;
+
+ dev_dbg(&spi->dev, "Ezport section erase @ 0x%06x...\n", address);
+
+ if (address & EZPORT_SECTOR_MASK)
+ return -EINVAL;
+
+ ret = ezport_write_enable(spi);
+ if (ret < 0)
+ return ret;
+
+ ret = spi_write(spi, query, sizeof(query));
+ if (ret < 0)
+ return ret;
+
+ return ezport_wait_write(spi, 200);
+}
+
+static int ezport_flash_transfer(struct spi_device *spi, u32 address,
+ const u8 *payload, size_t payload_size)
+{
+ struct spi_transfer xfers[2] = {};
+ u8 *command;
+ int ret;
+
+ dev_dbg(&spi->dev, "EzPort write %zu bytes @ 0x%06x...\n", payload_size, address);
+
+ ret = ezport_write_enable(spi);
+ if (ret < 0)
+ return ret;
+
+ command = kmalloc(4, GFP_KERNEL | GFP_DMA);
+ if (!command)
+ return -ENOMEM;
+
+ command[0] = EZPORT_CMD_SP;
+ command[1] = address >> 16;
+ command[2] = address >> 8;
+ command[3] = address >> 0;
+
+ xfers[0].tx_buf = command;
+ xfers[0].len = 4;
+
+ xfers[1].tx_buf = payload;
+ xfers[1].len = payload_size;
+
+ ret = spi_sync_transfer(spi, xfers, 2);
+ kfree(command);
+ if (ret < 0)
+ return ret;
+
+ return ezport_wait_write(spi, 40);
+}
+
+static int ezport_flash_compare(struct spi_device *spi, u32 address,
+ const u8 *payload, size_t payload_size)
+{
+ struct spi_transfer xfers[2] = {};
+ u8 *buffer;
+ int ret;
+
+ buffer = kmalloc(payload_size + 5, GFP_KERNEL | GFP_DMA);
+ if (!buffer)
+ return -ENOMEM;
+
+ buffer[0] = EZPORT_CMD_FAST_READ;
+ buffer[1] = address >> 16;
+ buffer[2] = address >> 8;
+ buffer[3] = address >> 0;
+
+ xfers[0].tx_buf = buffer;
+ xfers[0].len = 4;
+ xfers[0].speed_hz = ACHC_FAST_READ_FREQ_HZ;
+
+ xfers[1].rx_buf = buffer + 4;
+ xfers[1].len = payload_size + 1;
+ xfers[1].speed_hz = ACHC_FAST_READ_FREQ_HZ;
+
+ ret = spi_sync_transfer(spi, xfers, 2);
+ if (ret)
+ goto err;
+
+ /* FAST_READ receives one dummy byte before the real data */
+ ret = memcmp(payload, buffer + 4 + 1, payload_size);
+ if (ret) {
+ ret = -EBADMSG;
+ dev_dbg(&spi->dev, "Verfication failure @ %06x", address);
+ print_hex_dump_bytes("fw: ", DUMP_PREFIX_OFFSET, payload, payload_size);
+ print_hex_dump_bytes("dev: ", DUMP_PREFIX_OFFSET, buffer + 4, payload_size);
+ }
+
+err:
+ kfree(buffer);
+ return ret;
+}
+
+static int ezport_firmware_compare_data(struct spi_device *spi,
+ const u8 *data, size_t size)
+{
+ int ret;
+ size_t address = 0;
+ size_t transfer_size;
+
+ dev_dbg(&spi->dev, "EzPort compare data with %zu bytes...\n", size);
+
+ ret = ezport_get_status_register(spi);
+ if (ret < 0)
+ return ret;
+
+ if (ret & EZPORT_STATUS_FS) {
+ dev_info(&spi->dev, "Device is in secure mode (status=0x%02x)!\n", ret);
+ dev_info(&spi->dev, "FW verification is not possible\n");
+ return -EACCES;
+ }
+
+ while (size - address > 0) {
+ transfer_size = min((size_t) EZPORT_TRANSFER_SIZE, size - address);
+
+ ret = ezport_flash_compare(spi, address, data+address, transfer_size);
+ if (ret)
+ return ret;
+
+ address += transfer_size;
+ }
+
+ return 0;
+}
+
+static int ezport_firmware_flash_data(struct spi_device *spi,
+ const u8 *data, size_t size)
+{
+ int ret;
+ size_t address = 0;
+ size_t transfer_size;
+
+ dev_dbg(&spi->dev, "EzPort flash data with %zu bytes...\n", size);
+
+ ret = ezport_get_status_register(spi);
+ if (ret < 0)
+ return ret;
+
+ if (ret & EZPORT_STATUS_FS) {
+ ret = ezport_bulk_erase(spi);
+ if (ret < 0)
+ return ret;
+ if (ret & EZPORT_STATUS_FS)
+ return -EINVAL;
+ }
+
+ while (size - address > 0) {
+ if (!(address & EZPORT_SECTOR_MASK)) {
+ ret = ezport_section_erase(spi, address);
+ if (ret < 0)
+ return ret;
+ if (ret & EZPORT_STATUS_WIP || ret & EZPORT_STATUS_WEF)
+ return -EIO;
+ }
+
+ transfer_size = min((size_t) EZPORT_TRANSFER_SIZE, size - address);
+
+ ret = ezport_flash_transfer(spi, address,
+ data+address, transfer_size);
+ if (ret < 0)
+ return ret;
+ else if (ret & EZPORT_STATUS_WIP)
+ return -ETIMEDOUT;
+ else if (ret & EZPORT_STATUS_WEF)
+ return -EIO;
+
+ address += transfer_size;
+ }
+
+ dev_dbg(&spi->dev, "EzPort verify flashed data...\n");
+ ret = ezport_firmware_compare_data(spi, data, size);
+
+ /* allow missing FW verfication in secure mode */
+ if (ret == -EACCES)
+ ret = 0;
+
+ if (ret < 0)
+ dev_err(&spi->dev, "Failed to verify flashed data: %d\n", ret);
+
+ ret = ezport_soft_reset(spi);
+ if (ret < 0)
+ dev_warn(&spi->dev, "EzPort reset failed!\n");
+
+ return ret;
+}
+
+static int ezport_firmware_load(struct spi_device *spi, const char *fwname)
+{
+ const struct firmware *fw;
+ int ret;
+
+ ret = request_firmware(&fw, fwname, &spi->dev);
+ if (ret) {
+ dev_err(&spi->dev, "Could not get firmware: %d\n", ret);
+ return ret;
+ }
+
+ ret = ezport_firmware_flash_data(spi, fw->data, fw->size);
+
+ release_firmware(fw);
+
+ return ret;
+}
+
+/**
+ * ezport_flash - flash device firmware
+ * @spi: SPI device for NXP EzPort interface
+ * @reset: the gpio connected to the device reset pin
+ * @fwname: filename of the firmware that should be flashed
+ *
+ * Context: can sleep
+ *
+ * Return: 0 on success; negative errno on failure
+ */
+static int ezport_flash(struct spi_device *spi, struct gpio_desc *reset, const char *fwname)
+{
+ int ret;
+
+ ret = ezport_start_programming(spi, reset);
+ if (ret)
+ return ret;
+
+ ret = ezport_firmware_load(spi, fwname);
+
+ ezport_stop_programming(spi, reset);
+
+ if (ret)
+ dev_err(&spi->dev, "Failed to flash firmware: %d\n", ret);
+ else
+ dev_dbg(&spi->dev, "Finished FW flashing!\n");
+
+ return ret;
+}
+
+static ssize_t update_firmware_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct achc_data *achc = dev_get_drvdata(dev);
+ unsigned long value;
+ int ret;
+
+ ret = kstrtoul(buf, 0, &value);
+ if (ret < 0 || value != 1)
+ return -EINVAL;
+
+ mutex_lock(&achc->device_lock);
+ ret = ezport_flash(achc->ezport, achc->reset, "achc.bin");
+ mutex_unlock(&achc->device_lock);
+
+ if (ret < 0)
+ return ret;
+
+ return count;
+}
+static DEVICE_ATTR_WO(update_firmware);
+
+static ssize_t reset_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct achc_data *achc = dev_get_drvdata(dev);
+ int ret;
+
+ mutex_lock(&achc->device_lock);
+ ret = gpiod_get_value(achc->reset);
+ mutex_unlock(&achc->device_lock);
+
+ if (ret < 0)
+ return ret;
+
+ return sysfs_emit(buf, "%d\n", ret);
+}
+
+static ssize_t reset_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct achc_data *achc = dev_get_drvdata(dev);
+ unsigned long value;
+ int ret;
+
+ ret = kstrtoul(buf, 0, &value);
+ if (ret < 0 || value > 1)
+ return -EINVAL;
+
+ mutex_lock(&achc->device_lock);
+ gpiod_set_value(achc->reset, value);
+ mutex_unlock(&achc->device_lock);
+
+ return count;
+}
+static DEVICE_ATTR_RW(reset);
+
+static struct attribute *gehc_achc_attrs[] = {
+ &dev_attr_update_firmware.attr,
+ &dev_attr_reset.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(gehc_achc);
+
+static void unregister_ezport(void *data)
+{
+ struct spi_device *ezport = data;
+
+ spi_unregister_device(ezport);
+}
+
+static int gehc_achc_probe(struct spi_device *spi)
+{
+ struct achc_data *achc;
+ int ezport_reg, ret;
+
+ spi->max_speed_hz = ACHC_MAX_FREQ_HZ;
+ spi->bits_per_word = 8;
+ spi->mode = SPI_MODE_0;
+
+ achc = devm_kzalloc(&spi->dev, sizeof(*achc), GFP_KERNEL);
+ if (!achc)
+ return -ENOMEM;
+ spi_set_drvdata(spi, achc);
+ achc->main = spi;
+
+ mutex_init(&achc->device_lock);
+
+ ret = of_property_read_u32_index(spi->dev.of_node, "reg", 1, &ezport_reg);
+ if (ret)
+ return dev_err_probe(&spi->dev, ret, "missing second reg entry!\n");
+
+ achc->ezport = spi_new_ancillary_device(spi, ezport_reg);
+ if (IS_ERR(achc->ezport))
+ return PTR_ERR(achc->ezport);
+
+ ret = devm_add_action_or_reset(&spi->dev, unregister_ezport, achc->ezport);
+ if (ret)
+ return ret;
+
+ achc->reset = devm_gpiod_get(&spi->dev, "reset", GPIOD_OUT_LOW);
+ if (IS_ERR(achc->reset))
+ return dev_err_probe(&spi->dev, PTR_ERR(achc->reset), "Could not get reset gpio\n");
+
+ return 0;
+}
+
+static const struct spi_device_id gehc_achc_id[] = {
+ { "ge,achc", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, gehc_achc_id);
+
+static const struct of_device_id gehc_achc_of_match[] = {
+ { .compatible = "ge,achc" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, gehc_achc_of_match);
+
+static struct spi_driver gehc_achc_spi_driver = {
+ .driver = {
+ .name = "gehc-achc",
+ .of_match_table = gehc_achc_of_match,
+ .dev_groups = gehc_achc_groups,
+ },
+ .probe = gehc_achc_probe,
+ .id_table = gehc_achc_id,
+};
+module_spi_driver(gehc_achc_spi_driver);
+
+MODULE_DESCRIPTION("GEHC ACHC driver");
+MODULE_AUTHOR("Sebastian Reichel <sebastian.reichel@collabora.com>");
+MODULE_LICENSE("GPL");
@@ -677,7 +677,6 @@ static struct class *spidev_class;
static const struct of_device_id spidev_dt_ids[] = {
{ .compatible = "rohm,dh2228fv" },
{ .compatible = "lineartechnology,ltc2488" },
- { .compatible = "ge,achc" },
{ .compatible = "semtech,sx1301" },
{ .compatible = "lwn,bk4" },
{ .compatible = "dh,dhcom-board" },
General Electric Healthcare's PPD has a secondary processor from NXP's Kinetis K20 series. That device has two SPI chip selects: The main interface's behaviour depends on the loaded firmware and is currently unused. The secondary interface can be used to update the firmware using EzPort protocol. This is implemented by this driver using the kernel's firmware API. The firmware is being flashed into non-volatile flash memory, so it is enough to flash it once and not on every boot. Flashing will wear the flash memory (it has a life time of at least 10k programming cycles). At the same time only occasional FW updates are expected (like e.g. a BIOS update). Thus the firmware update is triggered via sysfs instead of doing it in the driver's probe routine like many other drivers. Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com> --- .../ABI/testing/sysfs-driver-ge-achc | 15 + drivers/misc/Kconfig | 12 + drivers/misc/Makefile | 1 + drivers/misc/gehc-achc.c | 565 ++++++++++++++++++ drivers/spi/spidev.c | 1 - 5 files changed, 593 insertions(+), 1 deletion(-) create mode 100644 Documentation/ABI/testing/sysfs-driver-ge-achc create mode 100644 drivers/misc/gehc-achc.c