From 8846739f52afa07e63395c80227dc544f54bd7b1 Mon Sep 17 00:00:00 2001 From: Johannes Thumshirn Date: Mon, 8 Jul 2024 17:49:28 +0200 Subject: [PATCH] spi: add ch341a usb2spi driver Add a driver for the QiHeng Electronics ch341a USB-to-SPI adapter. This driver is loosely based on the ch341a module from the flashrom project. Signed-off-by: Johannes Thumshirn Link: https://patch.msgid.link/20240708-spi-ch341a-v3-1-cf7f9b2c1e31@kernel.org Signed-off-by: Mark Brown --- drivers/spi/Kconfig | 6 + drivers/spi/Makefile | 1 + drivers/spi/spi-ch341.c | 241 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 248 insertions(+) create mode 100644 drivers/spi/spi-ch341.c diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index a2c99ff33e0a..ec1550c698d5 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -277,6 +277,12 @@ config SPI_CADENCE_XSPI device with a Cadence XSPI controller and want to access the Flash as an MTD device. +config SPI_CH341 + tristate "CH341 USB2SPI adapter" + depends on SPI_MASTER && USB + help + Enables the SPI controller on the CH341a USB to serial chip + config SPI_CLPS711X tristate "CLPS711X host SPI controller" depends on ARCH_CLPS711X || COMPILE_TEST diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index bcfb6efd88e0..a9b1bc259b68 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -39,6 +39,7 @@ obj-$(CONFIG_SPI_BUTTERFLY) += spi-butterfly.o obj-$(CONFIG_SPI_CADENCE) += spi-cadence.o obj-$(CONFIG_SPI_CADENCE_QUADSPI) += spi-cadence-quadspi.o obj-$(CONFIG_SPI_CADENCE_XSPI) += spi-cadence-xspi.o +obj-$(CONFIG_SPI_CH341) += spi-ch341.o obj-$(CONFIG_SPI_CLPS711X) += spi-clps711x.o obj-$(CONFIG_SPI_COLDFIRE_QSPI) += spi-coldfire-qspi.o obj-$(CONFIG_SPI_CS42L43) += spi-cs42l43.o diff --git a/drivers/spi/spi-ch341.c b/drivers/spi/spi-ch341.c new file mode 100644 index 000000000000..d2351812d310 --- /dev/null +++ b/drivers/spi/spi-ch341.c @@ -0,0 +1,241 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// QiHeng Electronics ch341a USB-to-SPI adapter driver +// +// Copyright (C) 2024 Johannes Thumshirn +// +// Based on ch341a_spi.c from the flashrom project. + +#include +#include +#include + +#define CH341_PACKET_LENGTH 32 +#define CH341_DEFAULT_TIMEOUT 1000 + +#define CH341A_CMD_UIO_STREAM 0xab + +#define CH341A_CMD_UIO_STM_END 0x20 +#define CH341A_CMD_UIO_STM_DIR 0x40 +#define CH341A_CMD_UIO_STM_OUT 0x80 + +#define CH341A_CMD_I2C_STREAM 0xaa +#define CH341A_CMD_I2C_STM_SET 0x60 +#define CH341A_CMD_I2C_STM_END 0x00 + +#define CH341A_CMD_SPI_STREAM 0xa8 + +#define CH341A_STM_I2C_100K 0x01 + +struct ch341_spi_dev { + struct spi_controller *ctrl; + struct usb_device *udev; + unsigned int write_pipe; + unsigned int read_pipe; + int rx_len; + void *rx_buf; + u8 *tx_buf; + struct urb *rx_urb; + struct spi_device *spidev; +}; + +static void ch341_set_cs(struct spi_device *spi, bool is_high) +{ + struct ch341_spi_dev *ch341 = + spi_controller_get_devdata(spi->controller); + int err; + + memset(ch341->tx_buf, 0, CH341_PACKET_LENGTH); + ch341->tx_buf[0] = CH341A_CMD_UIO_STREAM; + ch341->tx_buf[1] = CH341A_CMD_UIO_STM_OUT | (is_high ? 0x36 : 0x37); + + if (is_high) { + ch341->tx_buf[2] = CH341A_CMD_UIO_STM_DIR | 0x3f; + ch341->tx_buf[3] = CH341A_CMD_UIO_STM_END; + } else { + ch341->tx_buf[2] = CH341A_CMD_UIO_STM_END; + } + + err = usb_bulk_msg(ch341->udev, ch341->write_pipe, ch341->tx_buf, + (is_high ? 4 : 3), NULL, CH341_DEFAULT_TIMEOUT); + if (err) + dev_err(&spi->dev, + "error sending USB message for setting CS (%d)\n", err); +} + +static int ch341_transfer_one(struct spi_controller *host, + struct spi_device *spi, + struct spi_transfer *trans) +{ + struct ch341_spi_dev *ch341 = + spi_controller_get_devdata(spi->controller); + int len; + int ret; + + len = min(CH341_PACKET_LENGTH, trans->len + 1); + + memset(ch341->tx_buf, 0, CH341_PACKET_LENGTH); + + ch341->tx_buf[0] = CH341A_CMD_SPI_STREAM; + + memcpy(ch341->tx_buf + 1, trans->tx_buf, len); + + ret = usb_bulk_msg(ch341->udev, ch341->write_pipe, ch341->tx_buf, len, + NULL, CH341_DEFAULT_TIMEOUT); + if (ret) + return ret; + + return usb_bulk_msg(ch341->udev, ch341->read_pipe, trans->rx_buf, + len - 1, NULL, CH341_DEFAULT_TIMEOUT); +} + +static void ch341_recv(struct urb *urb) +{ + struct ch341_spi_dev *ch341 = urb->context; + struct usb_device *udev = ch341->udev; + + switch (urb->status) { + case 0: + /* success */ + break; + case -ENOENT: + case -ECONNRESET: + case -EPIPE: + case -ESHUTDOWN: + dev_dbg(&udev->dev, "rx urb terminated with status: %d\n", + urb->status); + return; + default: + dev_dbg(&udev->dev, "rx urb error: %d\n", urb->status); + break; + } +} + +static int ch341_config_stream(struct ch341_spi_dev *ch341) +{ + memset(ch341->tx_buf, 0, CH341_PACKET_LENGTH); + ch341->tx_buf[0] = CH341A_CMD_I2C_STREAM; + ch341->tx_buf[1] = CH341A_CMD_I2C_STM_SET | CH341A_STM_I2C_100K; + ch341->tx_buf[2] = CH341A_CMD_I2C_STM_END; + + return usb_bulk_msg(ch341->udev, ch341->write_pipe, ch341->tx_buf, 3, + NULL, CH341_DEFAULT_TIMEOUT); +} + +static int ch341_enable_pins(struct ch341_spi_dev *ch341, bool enable) +{ + memset(ch341->tx_buf, 0, CH341_PACKET_LENGTH); + ch341->tx_buf[0] = CH341A_CMD_UIO_STREAM; + ch341->tx_buf[1] = CH341A_CMD_UIO_STM_OUT | 0x37; + ch341->tx_buf[2] = CH341A_CMD_UIO_STM_DIR | (enable ? 0x3f : 0x00); + ch341->tx_buf[3] = CH341A_CMD_UIO_STM_END; + + return usb_bulk_msg(ch341->udev, ch341->write_pipe, ch341->tx_buf, 4, + NULL, CH341_DEFAULT_TIMEOUT); +} + +static struct spi_board_info chip = { + .modalias = "spi-ch341a", +}; + +static int ch341_probe(struct usb_interface *intf, + const struct usb_device_id *id) +{ + struct usb_device *udev = interface_to_usbdev(intf); + struct usb_endpoint_descriptor *in, *out; + struct ch341_spi_dev *ch341; + struct spi_controller *ctrl; + int ret; + + ret = usb_find_common_endpoints(intf->cur_altsetting, &in, &out, NULL, + NULL); + if (ret) + return ret; + + ctrl = devm_spi_alloc_master(&udev->dev, sizeof(struct ch341_spi_dev)); + if (!ctrl) + return -ENOMEM; + + ch341 = spi_controller_get_devdata(ctrl); + ch341->ctrl = ctrl; + ch341->udev = udev; + ch341->write_pipe = usb_sndbulkpipe(udev, usb_endpoint_num(out)); + ch341->read_pipe = usb_rcvbulkpipe(udev, usb_endpoint_num(in)); + + ch341->rx_len = usb_endpoint_maxp(in); + ch341->rx_buf = devm_kzalloc(&udev->dev, ch341->rx_len, GFP_KERNEL); + if (!ch341->rx_buf) + return -ENOMEM; + + ch341->rx_urb = usb_alloc_urb(0, GFP_KERNEL); + if (!ch341->rx_urb) + return -ENOMEM; + + ch341->tx_buf = + devm_kzalloc(&udev->dev, CH341_PACKET_LENGTH, GFP_KERNEL); + if (!ch341->tx_buf) + return -ENOMEM; + + usb_fill_bulk_urb(ch341->rx_urb, udev, ch341->read_pipe, ch341->rx_buf, + ch341->rx_len, ch341_recv, ch341); + + ret = usb_submit_urb(ch341->rx_urb, GFP_KERNEL); + if (ret) { + usb_free_urb(ch341->rx_urb); + return -ENOMEM; + } + + ctrl->bus_num = -1; + ctrl->mode_bits = SPI_CPHA; + ctrl->transfer_one = ch341_transfer_one; + ctrl->set_cs = ch341_set_cs; + ctrl->auto_runtime_pm = false; + + usb_set_intfdata(intf, ch341); + + ret = ch341_config_stream(ch341); + if (ret) + return ret; + + ret = ch341_enable_pins(ch341, true); + if (ret) + return ret; + + ret = spi_register_controller(ctrl); + if (ret) + return ret; + + ch341->spidev = spi_new_device(ctrl, &chip); + if (!ch341->spidev) + return -ENOMEM; + + return 0; +} + +static void ch341_disconnect(struct usb_interface *intf) +{ + struct ch341_spi_dev *ch341 = usb_get_intfdata(intf); + + spi_unregister_device(ch341->spidev); + spi_unregister_controller(ch341->ctrl); + ch341_enable_pins(ch341, false); + usb_free_urb(ch341->rx_urb); +} + +static const struct usb_device_id ch341_id_table[] = { + { USB_DEVICE(0x1a86, 0x5512) }, + { } +}; +MODULE_DEVICE_TABLE(usb, ch341_id_table); + +static struct usb_driver ch341a_usb_driver = { + .name = "spi-ch341", + .probe = ch341_probe, + .disconnect = ch341_disconnect, + .id_table = ch341_id_table, +}; +module_usb_driver(ch341a_usb_driver); + +MODULE_AUTHOR("Johannes Thumshirn "); +MODULE_DESCRIPTION("QiHeng Electronics ch341 USB2SPI"); +MODULE_LICENSE("GPL v2");