[PATCH v8 1/2] Serial: silabs si4455 serial driver

Jozsef Horvath
2021-01-12T10:20:10Z

This is a serial port driver for
Silicon Labs Si4455 Sub-GHz transciver.

The goal of this driver is to removing wires
between central(linux) device and remote serial devices/sensors,
but keeping the original user software.
It represents regular serial interface for the user space.

Datasheet: https://www.silabs.com/documents/public/data-sheets/Si4455.pdf

Guide: Documentation/driver-api/serial/si4455.rst

Signed-off-by: Jozsef Horvath <info@ministro.hu>
---

changes v1:
- fixed: drivers: serial: si4455: coding style
- fixed: drivers: serial: si4455: error checking and order
- fixed: drivers: serial: si4455: remove unnecessary compatibility
strings from si4455_dt_ids

changes v2:
- fixed: drivers: serial: si4455: coding style

changes v3:
- fixed: drivers: serial: si4455: coding style
- fixed: drivers: serial: si4455: replace device configuration procedure
(SI4455_IOC_SEZC ioctl call) with request_firmware(...).
The firmware name comes from dt (silabs,ez-config)
- fixed: drivers: serial: si4455: replace transmit/receive channel
select (SI4455_IOC_STXC/SI4455_IOC_SRXC ioctl calls)
with sysfs entries (tx_channel, rx_channel).
Initial values comes from dt (silabs,tx-channel and silabs,rx-channel)
- fixed: drivers: serial: si4455: replace package size setting
(SI4455_IOC_SSIZ ioctl call) with sysfs entry (package_size).
Initial value comes from dt (silabs,package-size)
- fixed: drivers: serial: si4455: replace getting last rssi
(SI4455_IOC_GRSSI ioctl call) with sysfs entry (current_rssi)
- fixed: drivers: serial: si4455: remove si4455_api.h
and custom ioctl definitions

changes v5:
- fixed: drivers: serial: si4455: coding style
- fixed: drivers: serial: si4455: remove struct si4455_one,
members moved to struct si4455_port
- fixed: drivers: serial: si4455: fix line endings in dev_err and
dev_dbg messages
- fixed: drivers: serial: si4455: remove unnecessary else { ... }
- fixed: drivers: serial: si4455: refactor si4455_do_work(...),
xmit circular buffer handling and start tx moved to
si4455_start_tx_xmit(...)
- fixed: drivers: serial: si4455: refactor si4455_configure
- fixed: drivers: serial: si4455: refactor interrupt handling,
remove unnecessary wrapper
- fixed: drivers: serial: si4455: modem line(si4455_get_mctrl)
and tx buffer status(si4455_tx_empty) conditions and signaling
- fixed: drivers: serial: si4455: remove unsafe int to pointer conversion

changes v6:
- fixed: drivers: serial: si4455: illegal characters in
MODULE_AUTHOR("...") Reported-by: kernel test robot <lkp@intel.com>

changes v7:
- added: drivers: serial: si4455: variable packet length support
- added: drivers: serial: si4455: extended error handling

changes v8:
- fixed: drivers: serial: si4455: removed unnecessary error checking around debugfs
- fixed: drivers: serial: si4455: removed unnecessary #ifdefs
- fixed: drivers: serial: kconfig: add missing module name to help text
- fixed: drivers: serial: si4455: device name ttySI changed to ttySSi
because of collosion. The ttySI is allocated alredy in devices.txt
- fixed: drivers: serial: si4455: revoved unnecessary administrative definitions
(major, minor)
- fixed: drivers: serial: si4455: definition PORT_SI4455 changed and moved to serial_core.h
- fixed: drivers: serial: si4455: silabs,tx-timeout property name changed
to silabs,tx-timeout-ms
---
Documentation/driver-api/serial/index.rst | 1 +
Documentation/driver-api/serial/si4455.rst | 216 +++
MAINTAINERS | 7 +
drivers/tty/serial/Kconfig | 11 +
drivers/tty/serial/Makefile | 1 +
drivers/tty/serial/si4455.c | 1660 ++++++++++++++++++++
include/uapi/linux/serial_core.h | 3 +
7 files changed, 1899 insertions(+)
create mode 100644 Documentation/driver-api/serial/si4455.rst
create mode 100644 drivers/tty/serial/si4455.c

diff --git a/Documentation/driver-api/serial/index.rst b/Documentation/driver-api/serial/index.rst
index 33ad10d05b26..2b71e87f1103 100644
--- a/Documentation/driver-api/serial/index.rst
+++ b/Documentation/driver-api/serial/index.rst
@@ -23,6 +23,7 @@ Serial drivers
rocket
serial-iso7816
serial-rs485
+ si4455

.. only:: subproject and html

diff --git a/Documentation/driver-api/serial/si4455.rst b/Documentation/driver-api/serial/si4455.rst
new file mode 100644
index 000000000000..f81c35c18067
--- /dev/null
+++ b/Documentation/driver-api/serial/si4455.rst
@@ -0,0 +1,216 @@
+.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+
+======================================
+Silicon Labs Si4455 serial port driver
+======================================
+
+This is a serial port driver for Silicon Labs Si4455 Sub-GHz transciver.
+
+The goal of this driver is to removing wires between central(linux) device and remote serial devices/sensors,
+but keeping the original user software.
+It represents regular serial interface for the user space.
+
+[0] - Datasheet: https://www.silabs.com/documents/public/data-sheets/Si4455.pdf
+
+Additional readings:
+
+* [1] - AN 692 Si4355/Si4455 PROGRAMMING GUIDE (https://www.silabs.com/documents/public/application-notes/AN692.pdf)
+* [2] - AN796 WIRELESS DEVELOPMENT SUITE GENERAL DESCRIPTION (https://www.silabs.com/documents/public/application-notes/AN796.pdf)
+* [3] - EZRadio REVB1A API (https://www.silabs.com/documents/public/application-notes/EZRadio_REVB1_API.zip)
+* [4] - EZRadio REVC2A API (https://www.silabs.com/documents/public/application-notes/EZRadio_REVC2_API.zip)
+* [5] - Using PART_INFO command to identify EZRadio/PRO part number (https://www.silabs.com/community/wireless/proprietary/knowledge-base.entry.html/2017/04/04/using_part_info_comm-XwP9)
+
+1. Device tree bindings
+=======================
+You can see the required parameters in silabs,si4455.yaml (Documentation/devicetree/bindings/serial/silabs,si4455.yaml)
+
+2. Device configuration(firmware)
+=================================
+
+2.1. Prerequirements
+^^^^^^^^^^^^^^^^^^^^
+
+To generate radio configuration, the Silicon Labs Wireless Development Suite
+(https://www.silabs.com/documents/login/software/WDS3-Setup.exe) is required.
+
+2.2. Generate
+^^^^^^^^^^^^^
+
+Before you start, see ref: [2]
+
+1. Start WDS
+2. Select *Simulate radio* option on startup screen
+3. Select *Si4455* and revision you have in *Select Radio* dialog
+4. Select *Radio Configuration Application* in *Application Manager*
+5. Select *Bidirectional packet* project in *Radio Configuration Application* dialog.
+6. Make your project specific configuration.
+7. Click *Generate source* than choose *Export custom project for third party IDE*
+
+2.3. Compile
+^^^^^^^^^^^^
+
+1. create ``radio_config/main.c`` with the following code::
+
+ #include <stdlib.h>
+ #include <stdio.h>
+ #include <stdint.h>
+ #include <unistd.h>
+ #include "radio.h"
+ #include "radio_config.h"
+ uint8_t Radio_Configuration_Data_Array[] = RADIO_CONFIGURATION_DATA_ARRAY;
+ int main (int argc, char ** argv)
+ {
+ write(1, Radio_Configuration_Data_Array, sizeof(Radio_Configuration_Data_Array));
+ }
+
+2. create ``radio_config/radio.h`` with the following code::
+
+ #ifndef RADIO_H_
+ #define RADIO_H_
+
+ #define RADIO_MAX_PACKET_LENGTH 64u
+
+ typedef struct
+ {
+ uint8_t *Radio_ConfigurationArray;
+
+ uint8_t Radio_ChannelNumber;
+ uint8_t Radio_PacketLength;
+ uint8_t Radio_State_After_Power_Up;
+
+ uint16_t Radio_Delay_Cnt_After_Reset;
+
+ uint8_t Radio_CustomPayload[RADIO_MAX_PACKET_LENGTH];
+ } tRadioConfiguration;
+ #endif /* RADIO_H_ */
+
+3. in case of **Chip revision C2** copy ``src\drivers\radio\Si4455\si4455_patch.h`` from project directory generated by WDS to ``radio_config/si4455_patch.h``
+4. copy ``src\application\radio_config.h`` from project directory generated by WDS to ``radio_config/radio_config.h``
+5. in case of **Chip revision C2** change the content of ``radio_config/radio_config.h``::
+
+ - #include "..\drivers\radio\Si4455\si4455_patch.h"
+ + #include "si4455_patch.h"
+
+6. compile
+
+ gcc radio_config/main.c -o radio_config/fwc
+
+7. run
+
+ radio_config/fwc > /lib/firmware/$(firmware-name)
+
+3. Device
+=========
+
+The driver instances are comes up under ``/dev`` as
+
+ /dev/ttySLX
+
+, where ``X`` is the index of instance.
+
+The driver supports only:
+
+* Char size: 8 bits
+* Handshake: None or RTSCTS.
+ RTSCTS preferred
+
+4. sysfs
+========
+
+The si4455 driver uses configuration parameters and maintains statistics inside sysfs filesystem.
+
+**current_rssi**:
+
+ Path:
+ /sys/class/tty/ttySLX/device/current_rssi
+
+ Description:
+ Shows the latest rssi value measured by chip.
+ To convert the value to dBm. See chapter *3.2.1. Received Signal Strength Indicator* in [0]
+
+**package_size**:
+
+ Path:
+ /sys/class/tty/ttySLX/device/package_size
+
+ Description:
+ Shows or stores the package size.
+ The new value applied immediately.
+ Variable package size (package_size = 0)
+
+**rx_channel**:
+
+ Path:
+ /sys/class/tty/ttySLX/device/rx_channel
+
+ Description:
+ Shows or stores the receive channel index.
+ The new value applied immediately.
+
+**tx_channel**:
+
+ Path:
+ /sys/class/tty/ttySLX/device/tx_channel
+
+ Description:
+ Shows or stores transmit channel index.
+ The new value will be used on next data transmit.
+
+**tx_timeout**:
+
+ Path:
+ /sys/class/tty/ttySLX/device/tx_timeout
+
+ Description:
+ Shows or stores the transmit timeout.
+ The new value will be used on next data transmit.
+
+5. debugfs
+^^^^^^^^^^
+
+The si4455 driver maintains statistics inside debugfs filesystem.
+
+**cts_error_count**:
+
+ Path:
+ /sys/kernel/debug/spiX.Y/si4455/cts_error_count
+
+ Description:
+ The numer of cts timeouts. In case of cts timeout, the driver reinitialize the chip.
+
+**tx_error_count**:
+
+ Path:
+ /sys/kernel/debug/spiX.Y/si4455/tx_error_count
+
+ Description:
+ The number of tx timeouts. In case of tx timeout, the driver restarts the last data transmission.
+
+**chip_rev**:
+
+ Path:
+ /sys/kernel/debug/spiX.Y/si4455/partinfo/chip_rev
+
+ Description:
+ The value of CHIPREV field in PART_INFO structure.
+ See *PART_INFO* command details in [3] or in [4]
+
+**rom_id**:
+
+ Path:
+ /sys/kernel/debug/spiX.Y/si4455/partinfo/rom_id
+
+ Description:
+ The value of ROMID field in PART_INFO structure.
+ See *PART_INFO* command details in [3] or in [4]
+ See ref [5]
+
+**part**:
+
+ Path:
+ /sys/kernel/debug/spiX.Y/si4455/partinfo/part
+
+ Description:
+ The value of PART field in PART_INFO structure.
+ See *PART_INFO* command details in [3] or in [4]
+ See ref [5]
\ No newline at end of file
diff --git a/MAINTAINERS b/MAINTAINERS
index a008b70f3c16..e6e9f2b1aecc 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15952,6 +15952,13 @@ M: Jérôme Pouiller <jerome.pouiller@silabs.com>
S: Supported
F: drivers/staging/wfx/

+SILICON LABS SI4455 SERIAL DRIVER
+M: Jozsef Horvath <info@ministro.hu>
+S: Maintained
+F: Documentation/devicetree/bindings/serial/silabs,si4455.yaml
+F: Documentation/driver-api/serial/si4455.rst
+F: drivers/tty/serial/si4455.c
+
SILICON MOTION SM712 FRAME BUFFER DRIVER
M: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
M: Teddy Wang <teddy.wang@siliconmotion.com>
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 28f22e58639c..e91cce1074df 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -1583,6 +1583,17 @@ config SERIAL_MILBEAUT_USIO_CONSOLE
receives all kernel messages and warnings and which allows logins in
single user mode).

+config SERIAL_SI4455
+ tristate "Si4455 support"
+ depends on SPI
+ select SERIAL_CORE
+ help
+ This driver is for Silicon Labs's Si4455 Sub-GHz transciver.
+ Say 'Y' here if you wish to use it as serial port.
+
+ To compile this driver as a module, choose M here: the
+ module will be called si4455.
+
endmenu

config SERIAL_MCTRL_GPIO
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index caf167f0c10a..f01ff43db1d6 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -89,6 +89,7 @@ obj-$(CONFIG_SERIAL_MPS2_UART) += mps2-uart.o
obj-$(CONFIG_SERIAL_OWL) += owl-uart.o
obj-$(CONFIG_SERIAL_RDA) += rda-uart.o
obj-$(CONFIG_SERIAL_MILBEAUT_USIO) += milbeaut_usio.o
+obj-$(CONFIG_SERIAL_SI4455) += si4455.o
obj-$(CONFIG_SERIAL_SIFIVE) += sifive.o

# GPIOLIB helpers for modem control lines
diff --git a/drivers/tty/serial/si4455.c b/drivers/tty/serial/si4455.c
new file mode 100644
index 000000000000..98f80fce3486
--- /dev/null
+++ b/drivers/tty/serial/si4455.c
@@ -0,0 +1,1660 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 Jozsef Horvath <info@ministro.hu>
+ *
+ */
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio/driver.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <linux/regmap.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/spi/spi.h>
+#include <linux/uaccess.h>
+#include <linux/string.h>
+#include <linux/firmware.h>
+#include <linux/timer.h>
+#include <linux/debugfs.h>
+
+#define SI4455_NAME "Si4455"
+#define SI4455_DEV_NAME "ttySSi"
+#define SI4455_UART_NRMAX 16
+#define SI4455_FIFO_SIZE 64
+
+#define SI4455_CMD_ID_EZCONFIG_CHECK 0x19
+#define SI4455_CMD_ID_PART_INFO 0x01
+#define SI4455_CMD_REPLY_COUNT_PART_INFO 9
+#define SI4455_CMD_ID_GET_INT_STATUS 0x20
+#define SI4455_CMD_REPLY_COUNT_GET_INT_STATUS 8
+#define SI4455_CMD_ID_FIFO_INFO 0x15
+#define SI4455_CMD_ARG_COUNT_FIFO_INFO 2
+#define SI4455_CMD_REPLY_COUNT_FIFO_INFO 2
+#define SI4455_CMD_FIFO_INFO_ARG_TX_BIT 0x01
+#define SI4455_CMD_FIFO_INFO_ARG_RX_BIT 0x02
+#define SI4455_CMD_ID_READ_CMD_BUFF 0x44
+#define SI4455_CMD_ID_READ_RX_FIFO 0x77
+#define SI4455_CMD_ID_WRITE_TX_FIFO 0x66
+#define SI4455_CMD_ID_START_RX 0x32
+#define SI4455_CMD_ARG_COUNT_START_RX 8
+#define SI4455_CMD_START_RX_RXTIMEOUT_STATE_RX 8
+#define SI4455_CMD_START_RX_RXVALID_STATE_SLEEP 1
+#define SI4455_CMD_START_RX_RXVALID_STATE_RX 8
+#define SI4455_CMD_START_RX_RXINVALID_STATE_RX 8
+#define SI4455_CMD_ID_START_TX 0x31
+#define SI4455_CMD_ARG_COUNT_START_TX 5
+#define SI4455_CMD_ID_CHANGE_STATE 0x34
+#define SI4455_CMD_ARG_COUNT_CHANGE_STATE 2
+#define SI4455_CMD_CHANGE_STATE_STATE_SLEEP 1
+#define SI4455_CMD_CHANGE_STATE_STATE_READY 3
+#define SI4455_CMD_CHANGE_STATE_STATE_RX 8
+#define SI4455_CMD_GET_CHIP_STATUS_ERROR_PEND_MASK 0x08
+#define SI4455_CMD_GET_CHIP_STATUS_ERROR_PEND_BIT 0x08
+#define SI4455_CMD_GET_INT_STATUS_RX_FIFO_AF_BIT 0x01
+#define SI4455_CMD_GET_INT_STATUS_TX_FIFO_AE_BIT 0x02
+#define SI4455_CMD_GET_INT_STATUS_PACKET_SENT_PEND_BIT 0x20
+#define SI4455_CMD_GET_INT_STATUS_PACKET_RX_PEND_BIT 0x10
+#define SI4455_CMD_GET_INT_STATUS_CRC_ERROR_BIT 0x08
+#define SI4455_CMD_GET_INT_STATUS_CHIP_RDY_BIT 0x04
+#define SI4455_CMD_GET_INT_STATUS_CMD_ERROR_BIT 0x08
+#define SI4455_CMD_GET_INT_STATUS_ST_CHANGED_BIT 0x10
+#define SI4455_CMD_GET_INT_STATUS_FIFO_UO_BIT 0x20
+#define SI4455_CMD_ID_GET_MODEM_STATUS 0x22
+#define SI4455_CMD_ARG_COUNT_GET_MODEM_STATUS 2
+#define SI4455_CMD_REPLY_COUNT_GET_MODEM_STATUS 8
+
+struct si4455_part_info {
+ u8 chip_rev;
+ u16 part;
+ u8 pbuild;
+ u16 id;
+ u8 customer;
+ u8 rom_id;
+ u8 bond;
+};
+
+struct si4455_int_status {
+ u8 int_pend;
+ u8 int_status;
+ u8 ph_pend;
+ u8 ph_status;
+ u8 modem_pend;
+ u8 modem_status;
+ u8 chip_pend;
+ u8 chip_status;
+};
+
+struct si4455_modem_status {
+ u8 modem_pend;
+ u8 modem_status;
+ u8 curr_rssi;
+ u8 latch_rssi;
+ u8 ant1_rssi;
+ u8 ant2_rssi;
+ u16 afc_freq_offset;
+};
+
+struct si4455_fifo_info {
+ u8 rx_fifo_count;
+ u8 tx_fifo_space;
+};
+
+struct si4455_port {
+ struct uart_port port;
+ struct dentry *dbgfs_dir;
+ struct work_struct tx_work;
+ struct work_struct tx_wd_work;
+ struct work_struct cts_wd_work;
+ struct timer_list tx_wd_timer;
+ struct timer_list cts_wd_timer;
+ struct mutex mutex; /* For syncing access to device */
+ struct gpio_desc *shdn_gpio;
+ struct si4455_part_info part_info;
+ struct si4455_modem_status modem_status;
+ u32 tx_channel;
+ u32 rx_channel;
+ u32 package_size;
+ u32 current_rssi;
+ u32 cts_error_count;
+ u32 tx_error_count;
+ int power_count;
+ u32 tx_wd_timeout;
+ u32 tx_pending_size;
+ char ez_fw_name[255];
+ bool connected;
+ bool suspended;
+ bool configured;
+ bool cts_error;
+ bool tx_pending;
+ bool rx_pending;
+ bool tx_stopped;
+ bool rx_stopped;
+};
+
+static struct uart_driver si4455_uart = {
+ .owner = THIS_MODULE,
+ .driver_name = SI4455_NAME,
+ .dev_name = SI4455_DEV_NAME,
+ .nr = SI4455_UART_NRMAX,
+};
+
+static DEFINE_MUTEX(si4455_ports_lock); /* race on probe */
+static DECLARE_BITMAP(si4455_port_lines, SI4455_UART_NRMAX);
+
+static int si4455_get_response(struct uart_port *port, int length, u8 *data)
+{
+ int ret;
+ u8 data_out[] = { SI4455_CMD_ID_READ_CMD_BUFF };
+ u8 *data_in;
+ struct spi_transfer xfer[2];
+ int timeout = 100;
+
+ if (length > 0 && !data)
+ return -EINVAL;
+
+ data_in = kzalloc(1 + length, GFP_KERNEL);
+ if (!data_in)
+ return -ENOMEM;
+
+ memset(&xfer, 0x00, sizeof(xfer));
+ xfer[0].tx_buf = data_out;
+ xfer[0].len = sizeof(data_out);
+ xfer[1].rx_buf = data_in;
+ xfer[1].len = 1 + length;
+
+ while (--timeout > 0) {
+ data_out[0] = SI4455_CMD_ID_READ_CMD_BUFF;
+ ret = spi_sync_transfer(to_spi_device(port->dev), xfer,
+ ARRAY_SIZE(xfer));
+ if (ret) {
+ dev_err(port->dev, "%s: spi_sync_transfer error (%i)\n", __func__, ret);
+ break;
+ }
+
+ if (data_in[0] == 0xFF) {
+ if (length > 0 && data)
+ memcpy(data, &data_in[1], length);
+
+ break;
+ }
+ usleep_range(100, 200);
+ }
+ if (!ret && timeout == 0) {
+ dev_err(port->dev, "%s: timeout\n", __func__);
+ ret = -EIO;
+ }
+ kfree(data_in);
+ return ret;
+}
+
+static int si4455_poll_cts(struct uart_port *port)
+{
+ int ret;
+ struct si4455_port *s = dev_get_drvdata(port->dev);
+
+ ret = si4455_get_response(port, 0, NULL);
+ if (ret == -EIO) {
+ s->cts_error_count++;
+ s->cts_error = true;
+ }
+ return ret;
+}
+
+static int si4455_send_command(struct uart_port *port, int length, u8 *data)
+{
+ int ret;
+
+ ret = si4455_poll_cts(port);
+ if (ret) {
+ dev_err(port->dev,
+ "%s: si4455_poll_cts error (%i)\n", __func__, ret);
+ return ret;
+ }
+
+ ret = spi_write(to_spi_device(port->dev), data, length);
+ if (ret) {
+ dev_err(port->dev,
+ "%s: spi_write error (%i)\n", __func__, ret);
+ }
+
+ return ret;
+}
+
+static int si4455_send_command_get_response(struct uart_port *port,
+ int out_length, u8 *data_out,
+ int in_length, u8 *data_in)
+{
+ int ret;
+
+ ret = si4455_send_command(port, out_length, data_out);
+ if (ret) {
+ dev_err(port->dev,
+ "%s: si4455_send_command error (%i)\n", __func__, ret);
+ return ret;
+ }
+
+ return si4455_get_response(port, in_length, data_in);
+}
+
+static int si4455_read_data(struct uart_port *port, u8 command, bool poll,
+ int length, u8 *data)
+{
+ int ret = 0;
+ u8 data_out[] = { command };
+ struct spi_transfer xfer[] = {
+ {
+ .tx_buf = data_out,
+ .len = sizeof(data_out),
+ }, {
+ .rx_buf = data,
+ .len = length,
+ }
+ };
+
+ if (poll) {
+ ret = si4455_poll_cts(port);
+ if (ret)
+ return ret;
+ }
+
+ ret = spi_sync_transfer(to_spi_device(port->dev),
+ xfer,
+ ARRAY_SIZE(xfer));
+ if (ret) {
+ dev_err(port->dev,
+ "%s: spi_sync_transfer error (%i)\n", __func__, ret);
+ }
+
+ return ret;
+}
+
+static int si4455_write_data(struct uart_port *port, u8 command, bool poll,
+ int length, const u8 *data)
+{
+ int ret = 0;
+ u8 *data_out;
+
+ if (poll) {
+ ret = si4455_poll_cts(port);
+ if (ret)
+ return ret;
+ }
+
+ data_out = kzalloc(1 + length, GFP_KERNEL);
+ if (!data_out)
+ return -ENOMEM;
+
+ data_out[0] = command;
+ memcpy(&data_out[1], data, length);
+ ret = spi_write(to_spi_device(port->dev), data_out, 1 + length);
+ if (ret) {
+ dev_err(port->dev,
+ "%s: spi_write error (%i)\n", __func__, ret);
+ }
+
+ kfree(data_out);
+
+ return ret;
+}
+
+static void si4455_set_power(struct si4455_port *priv, bool on)
+{
+ if (!priv->shdn_gpio)
+ return;
+
+ gpiod_direction_output(priv->shdn_gpio, 0);
+ if (on) {
+ usleep_range(14000, 15000);
+ gpiod_set_value(priv->shdn_gpio, 1);
+ usleep_range(14000, 15000);
+ }
+}
+
+static int si4455_s_power(struct device *dev, bool on)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+
+ if (s->power_count == !on)
+ si4455_set_power(s, on);
+ s->power_count += on ? 1 : -1;
+ WARN_ON(s->power_count < 0);
+
+ return 0;
+}
+
+static int si4455_get_part_info(struct uart_port *port,
+ struct si4455_part_info *result)
+{
+ int ret;
+ u8 data_out[] = { SI4455_CMD_ID_PART_INFO };
+ u8 data_in[SI4455_CMD_REPLY_COUNT_PART_INFO];
+
+ ret = si4455_send_command_get_response(port, sizeof(data_out), data_out,
+ sizeof(data_in), data_in);
+ if (ret) {
+ dev_err(port->dev,
+ "%s: si4455_send_command_get_response error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ result->chip_rev = data_in[0];
+ memcpy(&result->part, &data_in[1], sizeof(result->part));
+ result->pbuild = data_in[3];
+ memcpy(&result->id, &data_in[4], sizeof(result->id));
+ result->customer = data_in[6];
+ result->rom_id = data_in[7];
+ result->bond = data_in[8];
+
+ return 0;
+}
+
+static int si4455_get_int_status(struct uart_port *port, u8 ph_clear,
+ u8 modem_clear, u8 chip_clear,
+ struct si4455_int_status *result)
+{
+ int ret;
+ u8 data_out[] = {
+ SI4455_CMD_ID_GET_INT_STATUS,
+ ph_clear,
+ modem_clear,
+ chip_clear
+ };
+ u8 data_in[SI4455_CMD_REPLY_COUNT_GET_INT_STATUS];
+
+ ret = si4455_send_command_get_response(port, sizeof(data_out), data_out,
+ sizeof(data_in), data_in);
+ if (ret) {
+ dev_err(port->dev,
+ "%s: si4455_send_command_get_response error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ result->int_pend = data_in[0];
+ result->int_status = data_in[1];
+ result->ph_pend = data_in[2];
+ result->ph_status = data_in[3];
+ result->modem_pend = data_in[4];
+ result->modem_status = data_in[5];
+ result->chip_pend = data_in[6];
+ result->chip_status = data_in[7];
+
+ return 0;
+}
+
+static int si4455_get_modem_status(struct uart_port *port, u8 modem_clear,
+ struct si4455_modem_status *result)
+{
+ int ret;
+ u8 data_out[] = {
+ SI4455_CMD_ID_GET_MODEM_STATUS,
+ modem_clear,
+ };
+ u8 data_in[SI4455_CMD_REPLY_COUNT_GET_MODEM_STATUS];
+
+ ret = si4455_send_command_get_response(port, sizeof(data_out), data_out,
+ sizeof(data_in), data_in);
+ if (ret) {
+ dev_err(port->dev,
+ "%s: si4455_send_command_get_response error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ result->modem_pend = data_in[0];
+ result->modem_status = data_in[1];
+ result->curr_rssi = data_in[2];
+ result->latch_rssi = data_in[3];
+ result->ant1_rssi = data_in[4];
+ result->ant2_rssi = data_in[5];
+ memcpy(&result->afc_freq_offset, &data_in[6],
+ sizeof(result->afc_freq_offset));
+
+ return 0;
+}
+
+static int si4455_fifo_info(struct uart_port *port, u8 fifo,
+ struct si4455_fifo_info *result)
+{
+ int ret;
+ u8 data_out[SI4455_CMD_ARG_COUNT_FIFO_INFO] = {
+ SI4455_CMD_ID_FIFO_INFO, fifo
+ };
+ u8 data_in[SI4455_CMD_REPLY_COUNT_FIFO_INFO] = { 0 };
+
+ ret = si4455_send_command_get_response(port, sizeof(data_out), data_out,
+ sizeof(data_in), data_in);
+ if (ret) {
+ dev_err(port->dev,
+ "%s: si4455_send_command_get_response error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ result->rx_fifo_count = data_in[0];
+ result->tx_fifo_space = data_in[1];
+
+ return 0;
+}
+
+static int si4455_read_rx_fifo(struct uart_port *port, int length, u8 *data)
+{
+ return si4455_read_data(port, SI4455_CMD_ID_READ_RX_FIFO, false,
+ length, data);
+}
+
+static int si4455_write_tx_fifo(struct uart_port *port, int length, u8 *data)
+{
+ return si4455_write_data(port, SI4455_CMD_ID_WRITE_TX_FIFO, false,
+ length, data);
+}
+
+static int si4455_rx(struct uart_port *port, u32 channel, u8 condition,
+ u16 length, u8 next_state1, u8 next_state2,
+ u8 next_state3)
+{
+ u8 data_out[SI4455_CMD_ARG_COUNT_START_RX];
+
+ data_out[0] = SI4455_CMD_ID_START_RX;
+ data_out[1] = channel;
+ data_out[2] = condition;
+ data_out[3] = (u8)(length >> 8);
+ data_out[4] = (u8)(length);
+ data_out[5] = next_state1;
+ data_out[6] = next_state2;
+ data_out[7] = next_state3;
+
+ return si4455_send_command(port, SI4455_CMD_ARG_COUNT_START_RX,
+ data_out);
+}
+
+static int si4455_tx(struct uart_port *port, u8 channel, u8 condition,
+ u16 length)
+{
+ struct si4455_port *s = dev_get_drvdata(port->dev);
+ u8 data_out[SI4455_CMD_ARG_COUNT_START_TX + 1];
+ u8 out_length = SI4455_CMD_ARG_COUNT_START_TX;
+
+ if (s->part_info.rom_id == 6)
+ out_length += 1;
+
+ data_out[0] = SI4455_CMD_ID_START_TX;
+ data_out[1] = channel;
+ data_out[2] = condition;
+ data_out[3] = (u8)(length >> 8);
+ data_out[4] = (u8)(length);
+ if (s->part_info.rom_id == 6)
+ data_out[5] = 0x44;
+
+ return si4455_send_command(port, out_length, data_out);
+}
+
+static int si4455_change_state(struct uart_port *port, u8 next_state1)
+{
+ u8 data_out[SI4455_CMD_ARG_COUNT_CHANGE_STATE];
+
+ data_out[0] = SI4455_CMD_ID_CHANGE_STATE;
+ data_out[1] = (u8)next_state1;
+
+ return si4455_send_command(port, SI4455_CMD_ARG_COUNT_CHANGE_STATE,
+ data_out);
+}
+
+static int si4455_begin_tx(struct uart_port *port, u32 channel, int length,
+ u8 *data)
+{
+ int ret = 0;
+ struct si4455_int_status int_status = { 0 };
+ struct si4455_fifo_info fifo_info = { 0 };
+
+ if (length > SI4455_FIFO_SIZE || length < 0)
+ return -EINVAL;
+
+ ret = si4455_get_int_status(port, 0, 0, 0, &int_status);
+ if (ret) {
+ dev_err(port->dev, "%s: si4455_get_int_status error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ ret = si4455_fifo_info(port, SI4455_CMD_FIFO_INFO_ARG_TX_BIT,
+ &fifo_info);
+ if (ret) {
+ dev_err(port->dev, "%s: si4455_fifo_info error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ ret = si4455_write_tx_fifo(port, (u16)length, data);
+ if (ret) {
+ dev_err(port->dev, "%s: si4455_write_tx_fifo error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ ret = si4455_tx(port, channel, 0x10, length);
+ if (ret) {
+ dev_err(port->dev, "%s: si4455_tx error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int si4455_end_tx(struct uart_port *port)
+{
+ int ret = 0;
+ struct si4455_int_status int_status = { 0 };
+
+ ret = si4455_get_int_status(port, 0, 0, 0, &int_status);
+ if (ret) {
+ dev_err(port->dev, "%s: si4455_get_int_status error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int si4455_begin_rx(struct uart_port *port, u32 channel, u32 length)
+{
+ struct si4455_port *s = dev_get_drvdata(port->dev);
+ int ret = 0;
+ struct si4455_int_status int_status = { 0 };
+ struct si4455_fifo_info fifo_info = { 0 };
+
+ ret = si4455_get_int_status(port, 0, 0, 0, &int_status);
+ if (ret) {
+ dev_err(port->dev, "%s: si4455_get_int_status error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ ret = si4455_fifo_info(port, SI4455_CMD_FIFO_INFO_ARG_RX_BIT,
+ &fifo_info);
+ if (ret) {
+ dev_err(port->dev, "%s: si4455_fifo_info error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ if (s->rx_stopped)
+ return 0;
+
+ ret = si4455_rx(port, channel, 0x00, length,
+ SI4455_CMD_START_RX_RXTIMEOUT_STATE_RX,
+ SI4455_CMD_START_RX_RXVALID_STATE_RX,
+ SI4455_CMD_START_RX_RXINVALID_STATE_RX);
+ if (ret) {
+ dev_err(port->dev, "%s: si4455_rx error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int si4455_end_rx(struct uart_port *port, u32 length, u8 *data)
+{
+ return si4455_read_rx_fifo(port, length, data);
+}
+
+static int si4455_configure(struct uart_port *port, const u8 *configuration_data)
+{
+ int ret = 0;
+ u8 col;
+ u8 response;
+ u8 count;
+ u8 cmd;
+ struct si4455_int_status int_status = { 0 };
+ u8 radio_cmd[16];
+
+ /*
+ * While cycle as far as the pointer points to a command
+ */
+ while (*configuration_data != 0x00) {
+ /*
+ * Commands structure in the array:
+ * --------------------------------
+ * LEN | <LEN length of data>
+ */
+ count = *configuration_data++;
+ cmd = *configuration_data;
+ dev_dbg(port->dev, "%s: count (%u), cmd (%u)\n",
+ __func__, count, cmd);
+
+ if (count > 16 && count <= 128 && cmd == SI4455_CMD_ID_WRITE_TX_FIFO) {
+ /*
+ * Load array to the device
+ */
+ configuration_data++;
+ ret = si4455_write_data(port, SI4455_CMD_ID_WRITE_TX_FIFO,
+ true, count - 1, configuration_data);
+ if (ret) {
+ dev_err(port->dev, "%s: si4455_write_data error (%i)\n",
+ __func__, ret);
+ break;
+ }
+
+ /*
+ * Point to the next command
+ */
+ configuration_data += count - 1;
+
+ /*
+ * Continue command interpreter
+ */
+ continue;
+ } else if (count > 16) {
+ /*
+ * Number of command bytes exceeds
+ * maximal allowable length
+ */
+ ret = -EINVAL;
+ break;
+ }
+
+ for (col = 0u; col < count; col++) {
+ radio_cmd[col] = *configuration_data;
+ configuration_data++;
+ }
+
+ dev_dbg(port->dev, "%s: radio_cmd[0] (%u)\n", __func__, radio_cmd[0]);
+ ret = si4455_send_command_get_response(port, count, radio_cmd,
+ 1, &response);
+ if (ret) {
+ dev_err(port->dev,
+ "%s: si4455_send_command_get_response error (%i)\n",
+ __func__, ret);
+ break;
+ }
+
+ /*
+ * Check response byte of EZCONFIG_CHECK command
+ */
+ if (radio_cmd[0] == SI4455_CMD_ID_EZCONFIG_CHECK) {
+ if (response) {
+ /*
+ * Number of command bytes exceeds
+ * maximal allowable length
+ */
+ ret = -EIO;
+ dev_err(port->dev, "%s: EZConfig check error (%i)\n",
+ __func__, radio_cmd[0]);
+ break;
+ }
+ }
+
+ /*
+ * Get and clear all interrupts. An error has occurred...
+ */
+ si4455_get_int_status(port, 0, 0, 0, &int_status);
+ if (int_status.chip_pend
+ & SI4455_CMD_GET_CHIP_STATUS_ERROR_PEND_MASK) {
+ ret = -EIO;
+ dev_err(port->dev, "%s: chip error (%i)\n",
+ __func__, int_status.chip_pend);
+ break;
+ }
+ }
+
+ return ret;
+}
+
+static int si4455_re_configure(struct uart_port *port, const struct firmware *configuration)
+{
+ int ret = 0;
+ struct si4455_port *s = dev_get_drvdata(port->dev);
+
+ s->configured = 0;
+ if (s->power_count == 0)
+ si4455_s_power(port->dev, true);
+
+ ret = si4455_configure(port, configuration->data);
+ if (ret == 0) {
+ s->configured = true;
+ s->cts_error = false;
+ }
+ return ret;
+}
+
+static int si4455_start_tx_xmit(struct uart_port *port)
+{
+ int ret;
+ struct si4455_port *s = dev_get_drvdata(port->dev);
+ struct circ_buf *xmit = &port->state->xmit;
+ u32 tx_pending;
+ u32 tx_to_end;
+ u8 *data;
+ u8 *payload;
+ u32 max_length;
+
+ if (s->tx_stopped)
+ return 0;
+
+ tx_pending = uart_circ_chars_pending(xmit);
+ if (tx_pending == 0 || tx_pending < s->package_size)
+ return 0;
+
+ max_length = (s->package_size == 0) ? SI4455_FIFO_SIZE - 3 : s->package_size;
+ tx_pending = (tx_pending > max_length) ? max_length : tx_pending;
+ if (s->package_size == 0)
+ data = kzalloc(tx_pending + 1, GFP_KERNEL);
+ else
+ data = kzalloc(tx_pending, GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ if (s->package_size == 0) {
+ data[0] = tx_pending;
+ payload = &data[1];
+ } else {
+ payload = data;
+ }
+
+ tx_to_end = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
+ if (tx_to_end < tx_pending) {
+ memcpy(payload, xmit->buf + xmit->tail, tx_to_end);
+ memcpy(&payload[tx_to_end], xmit->buf, tx_pending - tx_to_end);
+ } else {
+ memcpy(payload, xmit->buf + xmit->tail, tx_pending);
+ }
+
+ if (s->package_size == 0)
+ ret = si4455_begin_tx(port, s->tx_channel, tx_pending + 1, data);
+ else
+ ret = si4455_begin_tx(port, s->tx_channel, tx_pending, data);
+ if (!ret) {
+ s->tx_pending = true;
+ s->tx_pending_size = tx_pending;
+ uart_handle_cts_change(&s->port, 0);
+ mod_timer(&s->tx_wd_timer, jiffies + msecs_to_jiffies(s->tx_wd_timeout));
+ }
+
+ kfree(data);
+
+ return ret;
+}
+
+static int si4455_cancel_tx(struct uart_port *port)
+{
+ int ret = 0;
+ struct si4455_port *s = dev_get_drvdata(port->dev);
+
+ if (s->tx_pending) {
+ si4455_end_tx(port);
+ s->tx_pending = false;
+ s->tx_pending_size = 0;
+ uart_handle_cts_change(&s->port, TIOCM_CTS);
+ ret = si4455_change_state(port, SI4455_CMD_CHANGE_STATE_STATE_SLEEP);
+ }
+ return ret;
+}
+
+static int si4455_do_work(struct uart_port *port)
+{
+ int ret = 0;
+ struct si4455_port *s = dev_get_drvdata(port->dev);
+ struct circ_buf *xmit = &port->state->xmit;
+
+ mutex_lock(&s->mutex);
+ if (!s->suspended && s->connected && s->configured && s->power_count > 0) {
+ if (!(uart_circ_empty(xmit) || uart_tx_stopped(port) || s->tx_pending))
+ ret = si4455_start_tx_xmit(port);
+
+ if (!ret && !s->tx_pending)
+ ret = si4455_begin_rx(port, s->rx_channel, s->package_size);
+ }
+ mutex_unlock(&s->mutex);
+ return ret;
+}
+
+static void si4455_handle_rx_pend(struct si4455_port *s, struct si4455_fifo_info *fifo_info)
+{
+ struct uart_port *port = &s->port;
+ u8 *data;
+ int sret = 0;
+ int i = 0;
+ u32 length;
+
+ length = (s->package_size == 0) ? fifo_info->rx_fifo_count : s->package_size;
+
+ data = kzalloc(length, GFP_KERNEL);
+ if (!data)
+ return;
+
+ sret = si4455_end_rx(port, length, data);
+ if (sret) {
+ dev_err(port->dev, "%s: si4455_end_rx error (%i)\n",
+ __func__, sret);
+ } else {
+ if (!s->rx_stopped) {
+ for (i = 0; i < length; i++) {
+ uart_insert_char(port, 0, 0, data[i], TTY_NORMAL);
+ port->icount.rx++;
+ }
+ tty_flip_buffer_push(&port->state->port);
+ }
+ }
+ kfree(data);
+}
+
+static void si4455_handle_tx_pend(struct si4455_port *s)
+{
+ struct uart_port *port = &s->port;
+ struct circ_buf *xmit = &port->state->xmit;
+ u32 sent;
+
+ if (s->tx_pending) {
+ sent = (s->package_size == 0) ? s->tx_pending_size
+ : s->package_size;
+ port->icount.tx += sent;
+ xmit->tail = (xmit->tail + sent) & (UART_XMIT_SIZE - 1);
+ si4455_end_tx(port);
+ s->tx_pending = 0;
+ s->tx_pending_size = 0;
+ uart_handle_cts_change(&s->port, TIOCM_CTS);
+ }
+}
+
+static irqreturn_t si4455_ist(int irq, void *dev_id)
+{
+ struct si4455_port *s = (struct si4455_port *)dev_id;
+ struct uart_port *port = &s->port;
+ int ret;
+ struct si4455_int_status int_status = { 0 };
+ struct si4455_fifo_info fifo_info = { 0 };
+ bool have_to_do = false;
+
+ if (s->suspended || !s->connected || !s->configured || s->power_count == 0)
+ return IRQ_NONE;
+
+ mutex_lock(&s->mutex);
+ ret = si4455_get_int_status(port, 0, 0, 0, &int_status);
+ if (ret) {
+ mutex_unlock(&s->mutex);
+ return IRQ_NONE;
+ }
+
+ dev_dbg(port->dev, "%s: int_pend: 0x%x\n", __func__, int_status.int_pend);
+ dev_dbg(port->dev, "%s: int_status: 0x%x\n", __func__, int_status.int_status);
+ dev_dbg(port->dev, "%s: ph_pend: 0x%x\n", __func__, int_status.ph_pend);
+ dev_dbg(port->dev, "%s: ph_status: 0x%x\n", __func__, int_status.ph_status);
+ dev_dbg(port->dev, "%s: modem_pend: 0x%x\n", __func__, int_status.modem_pend);
+ dev_dbg(port->dev, "%s: modem_status: 0x%x\n", __func__, int_status.modem_status);
+ dev_dbg(port->dev, "%s: chip_pend: 0x%x\n", __func__, int_status.chip_pend);
+ dev_dbg(port->dev, "%s: chip_status: 0x%x\n", __func__, int_status.chip_status);
+
+ if (int_status.chip_pend & SI4455_CMD_GET_CHIP_STATUS_ERROR_PEND_BIT) {
+ dev_err(port->dev, "%s: chip_pend:CMD_ERROR_PEND\n", __func__);
+ si4455_change_state(port, SI4455_CMD_CHANGE_STATE_STATE_SLEEP);
+ si4455_fifo_info(&s->port, SI4455_CMD_FIFO_INFO_ARG_RX_BIT,
+ &fifo_info);
+ have_to_do = true;
+ } else if (int_status.ph_pend & SI4455_CMD_GET_INT_STATUS_PACKET_SENT_PEND_BIT) {
+ dev_dbg(port->dev, "%s: ph_pend:PACKET_SENT_PEND\n", __func__);
+ si4455_change_state(port, SI4455_CMD_CHANGE_STATE_STATE_SLEEP);
+ si4455_handle_tx_pend(s);
+ have_to_do = true;
+ } else if (int_status.ph_pend & SI4455_CMD_GET_INT_STATUS_PACKET_RX_PEND_BIT) {
+ dev_dbg(port->dev, "%s: ph_pend:PACKET_RX_PEND\n", __func__);
+ si4455_get_modem_status(port, 0, &s->modem_status);
+ s->current_rssi = s->modem_status.curr_rssi;
+ si4455_change_state(port, SI4455_CMD_CHANGE_STATE_STATE_SLEEP);
+ si4455_fifo_info(port, 0, &fifo_info);
+ si4455_handle_rx_pend(s, &fifo_info);
+ have_to_do = true;
+ } else if (int_status.ph_pend & SI4455_CMD_GET_INT_STATUS_CRC_ERROR_BIT) {
+ dev_dbg(port->dev, "%s: ph_pend:CRC_ERROR_PEND\n", __func__);
+ si4455_change_state(port, SI4455_CMD_CHANGE_STATE_STATE_SLEEP);
+ si4455_fifo_info(&s->port, SI4455_CMD_FIFO_INFO_ARG_RX_BIT,
+ &fifo_info);
+ have_to_do = true;
+ }
+ mutex_unlock(&s->mutex);
+ if (have_to_do)
+ si4455_do_work(port);
+ return IRQ_HANDLED;
+}
+
+static void si4455_tx_wd_event(struct timer_list *t)
+{
+ struct si4455_port *s = from_timer(s, t, tx_wd_timer);
+
+ if (s->tx_pending)
+ schedule_work(&s->tx_wd_work);
+}
+
+static void si4455_tx_wd_proc(struct work_struct *ws)
+{
+ struct si4455_port *s = container_of(ws, struct si4455_port, tx_wd_work);
+ bool have_to_work = false;
+
+ mutex_lock(&s->mutex);
+ if (s->connected && s->tx_pending) {
+ si4455_cancel_tx(&s->port);
+ s->tx_error_count++;
+ have_to_work = true;
+ dev_err(s->port.dev,
+ "%s: curent transmit operation interrupted by wd timeout\n",
+ __func__);
+ }
+ mutex_unlock(&s->mutex);
+
+ if (have_to_work)
+ si4455_do_work(&s->port);
+}
+
+static void si4455_cts_wd_event(struct timer_list *t)
+{
+ struct si4455_port *s = from_timer(s, t, cts_wd_timer);
+
+ if (s->cts_error)
+ schedule_work(&s->cts_wd_work);
+ else
+ mod_timer(&s->cts_wd_timer, jiffies + msecs_to_jiffies(100));
+}
+
+static void si4455_cts_wd_proc(struct work_struct *ws)
+{
+ struct si4455_port *s = container_of(ws, struct si4455_port, cts_wd_work);
+ const struct firmware *ez_fw = NULL;
+ bool have_to_work = false;
+ int ret;
+
+ mutex_lock(&s->mutex);
+ if (s->cts_error) {
+ dev_err(s->port.dev, "%s: interface recovery\n", __func__);
+ ret = request_firmware(&ez_fw, s->ez_fw_name, s->port.dev);
+ if (ret) {
+ dev_err(s->port.dev, "%s: firmware(%s) request error (%i)\n",
+ __func__, s->ez_fw_name, ret);
+ } else {
+ si4455_s_power(s->port.dev, false);
+ ret = si4455_re_configure(&s->port, ez_fw);
+ release_firmware(ez_fw);
+ if (ret) {
+ dev_err(s->port.dev, "%s: device configuration error (%i)\n",
+ __func__, ret);
+ }
+ }
+ have_to_work = !ret;
+ }
+ if (s->connected)
+ mod_timer(&s->cts_wd_timer, jiffies + msecs_to_jiffies(100));
+ mutex_unlock(&s->mutex);
+
+ if (have_to_work)
+ si4455_do_work(&s->port);
+}
+
+static void si4455_tx_proc(struct work_struct *ws)
+{
+ struct si4455_port *s = container_of(ws, struct si4455_port, tx_work);
+
+ si4455_do_work(&s->port);
+}
+
+static unsigned int si4455_tx_empty(struct uart_port *port)
+{
+ struct si4455_port *s = dev_get_drvdata(port->dev);
+
+ return s->tx_pending ? 0 : TIOCSER_TEMT;
+}
+
+static unsigned int si4455_get_mctrl(struct uart_port *port)
+{
+ int ret;
+ struct si4455_port *s = dev_get_drvdata(port->dev);
+
+ /*
+ * there is no a continuous real "carrier" like on phone line,
+ * but after configuration, the interface is ready to use the physical
+ * transport channel
+ */
+ ret = s->configured ? TIOCM_CAR | TIOCM_DSR : 0;
+ ret |= s->tx_pending ? 0 : TIOCM_CTS;
+
+ return ret;
+}
+
+static void si4455_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+}
+
+static void si4455_set_termios(struct uart_port *port, struct ktermios *termios,
+ struct ktermios *old)
+{
+ dev_dbg(port->dev, "termios->c_iflag = 0x%x", termios->c_iflag);
+ dev_dbg(port->dev, "termios->c_oflag = 0x%x", termios->c_oflag);
+ dev_dbg(port->dev, "termios->c_cflag = 0x%x", termios->c_cflag);
+ dev_dbg(port->dev, "termios->c_lflag = 0x%x", termios->c_lflag);
+ dev_dbg(port->dev, "termios->c_ispeed = %u", termios->c_ispeed);
+ dev_dbg(port->dev, "termios->c_ospeed = %u", termios->c_ospeed);
+ if ((termios->c_cflag & CSIZE) != CS8)
+ dev_err(port->dev, "%s: CSIZE must be CS8\n", __func__);
+}
+
+static int si4455_startup(struct uart_port *port)
+{
+ struct si4455_port *s = dev_get_drvdata(port->dev);
+
+ mutex_lock(&s->mutex);
+ s->tx_pending = false;
+ s->tx_stopped = false;
+ s->rx_stopped = false;
+ s->connected = true;
+ mod_timer(&s->cts_wd_timer, jiffies + msecs_to_jiffies(100));
+ mutex_unlock(&s->mutex);
+ return si4455_do_work(port);
+}
+
+static void si4455_shutdown(struct uart_port *port)
+{
+ struct si4455_port *s = dev_get_drvdata(port->dev);
+
+ mutex_lock(&s->mutex);
+ del_timer_sync(&s->tx_wd_timer);
+ del_timer_sync(&s->cts_wd_timer);
+ s->connected = false;
+ si4455_change_state(&s->port, SI4455_CMD_CHANGE_STATE_STATE_SLEEP);
+ mutex_unlock(&s->mutex);
+}
+
+static const char *si4455_type(struct uart_port *port)
+{
+ struct si4455_port *s = dev_get_drvdata(port->dev);
+
+ if (port->type != PORT_SI4455)
+ return NULL;
+ if (s->part_info.rom_id == 3)
+ return "SI4455-B1A";
+ else if (s->part_info.rom_id == 6)
+ return "SI4455-C2A";
+
+ return "SI4455(UNKNOWN-REV)";
+}
+
+static void si4455_config_port(struct uart_port *port, int flags)
+{
+ if (flags & UART_CONFIG_TYPE)
+ port->type = PORT_SI4455;
+}
+
+static int si4455_verify_port(struct uart_port *port, struct serial_struct *s)
+{
+ if (s->type != PORT_UNKNOWN && s->type != PORT_SI4455)
+ return -EINVAL;
+
+ if (s->irq != port->irq)
+ return -EINVAL;
+
+ return 0;
+}
+
+static void si4455_start_tx(struct uart_port *port)
+{
+ struct si4455_port *s = container_of(port, struct si4455_port, port);
+
+ s->tx_stopped = false;
+ schedule_work(&s->tx_work);
+}
+
+static void si4455_stop_tx(struct uart_port *port)
+{
+ struct si4455_port *s = container_of(port, struct si4455_port, port);
+
+ s->tx_stopped = true;
+}
+
+static void si4455_stop_rx(struct uart_port *port)
+{
+ struct si4455_port *s = container_of(port, struct si4455_port, port);
+
+ mutex_lock(&s->mutex);
+ s->rx_stopped = true;
+ si4455_change_state(&s->port, SI4455_CMD_CHANGE_STATE_STATE_SLEEP);
+ mutex_unlock(&s->mutex);
+}
+
+static const struct uart_ops si4455_ops = {
+ .tx_empty = si4455_tx_empty,
+ /*
+ * set_mctrl: required by serial_core, but not used
+ */
+ .set_mctrl = si4455_set_mctrl,
+ .get_mctrl = si4455_get_mctrl,
+ .stop_tx = si4455_stop_tx,
+ .start_tx = si4455_start_tx,
+ .stop_rx = si4455_stop_rx,
+ .startup = si4455_startup,
+ .shutdown = si4455_shutdown,
+ .set_termios = si4455_set_termios,
+ .type = si4455_type,
+ .config_port = si4455_config_port,
+ .verify_port = si4455_verify_port,
+};
+
+static void si4455_debugfs_init(struct device *dev)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+ struct dentry *dbgfs_si_dir;
+ struct dentry *dbgfs_partinfo_dir;
+
+ s->dbgfs_dir = debugfs_create_dir(dev_name(dev), NULL);
+
+ dbgfs_si_dir = debugfs_create_dir("si4455", s->dbgfs_dir);
+
+ debugfs_create_u32("cts_error_count", 0444, dbgfs_si_dir,
+ &s->cts_error_count);
+
+ debugfs_create_u32("tx_error_count", 0444, dbgfs_si_dir,
+ &s->tx_error_count);
+
+ dbgfs_partinfo_dir = debugfs_create_dir("partinfo", dbgfs_si_dir);
+
+ debugfs_create_u8("chip_rev", 0444, dbgfs_partinfo_dir,
+ &s->part_info.chip_rev);
+
+ debugfs_create_u8("rom_id", 0444, dbgfs_partinfo_dir,
+ &s->part_info.rom_id);
+
+ debugfs_create_u16("part", 0444, dbgfs_partinfo_dir,
+ &s->part_info.part);
+}
+
+static void si4455_debugfs_clear(struct device *dev)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+
+ debugfs_remove_recursive(s->dbgfs_dir);
+}
+
+static int __maybe_unused si4455_suspend(struct device *dev)
+{
+ int ret;
+ struct si4455_port *s = dev_get_drvdata(dev);
+
+ mutex_lock(&s->mutex);
+ ret = si4455_cancel_tx(&s->port);
+ if (ret) {
+ mutex_unlock(&s->mutex);
+ dev_err(dev, "%s: si4455_cancel_tx error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ ret = si4455_change_state(&s->port, SI4455_CMD_CHANGE_STATE_STATE_SLEEP);
+ s->suspended = !ret;
+ mutex_unlock(&s->mutex);
+
+ if (ret) {
+ dev_err(dev, "%s: si4455_change_state error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ return uart_suspend_port(&si4455_uart, &s->port);
+}
+
+static int __maybe_unused si4455_resume(struct device *dev)
+{
+ int ret;
+ struct si4455_port *s = dev_get_drvdata(dev);
+
+ ret = uart_resume_port(&si4455_uart, &s->port);
+ if (ret) {
+ dev_err(dev, "%s: uart_resume_port error (%i)\n",
+ __func__, ret);
+ return ret;
+ }
+
+ s->suspended = false;
+ s->rx_stopped = false;
+
+ return si4455_do_work(&s->port);
+}
+
+static SIMPLE_DEV_PM_OPS(si4455_pm_ops, si4455_suspend, si4455_resume);
+
+static ssize_t package_size_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", s->package_size);
+}
+
+static ssize_t package_size_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ if (val > SI4455_FIFO_SIZE)
+ return -EINVAL;
+
+ s->package_size = val;
+ ret = si4455_do_work(&s->port);
+
+ return ret ? ret : count;
+}
+
+/*
+ * package_size: rw sysfs entry.
+ * Sets or returns the package size.
+ * The new value applied immediately.
+ * Variable package size (package_size == 0)
+ * currently not supported by driver.
+ */
+static DEVICE_ATTR_RW(package_size);
+
+static ssize_t rx_channel_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", s->rx_channel);
+}
+
+static ssize_t rx_channel_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ s->rx_channel = val;
+ ret = si4455_do_work(&s->port);
+
+ return ret ? ret : count;
+}
+
+/*
+ * rx_channel: rw sysfs entry.
+ * Sets or returns the receive channel index.
+ * The new value applied immediately.
+ */
+static DEVICE_ATTR_RW(rx_channel);
+
+static ssize_t tx_channel_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", s->tx_channel);
+}
+
+static ssize_t tx_channel_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ s->tx_channel = val;
+ ret = si4455_do_work(&s->port);
+
+ return ret ? ret : count;
+}
+
+/*
+ * tx_channel: rw sysfs entry.
+ * Sets or returns the transmit channel index.
+ * The new value will be used on next data transmit.
+ */
+static DEVICE_ATTR_RW(tx_channel);
+
+static ssize_t tx_timeout_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", s->tx_wd_timeout);
+}
+
+static ssize_t tx_timeout_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ s->tx_wd_timeout = val;
+ ret = si4455_do_work(&s->port);
+
+ return ret ? ret : count;
+}
+
+/*
+ * tx_timeout: rw sysfs entry.
+ * Sets or returns the transmit timeout.
+ * The new value will be used on next data transmit.
+ */
+static DEVICE_ATTR_RW(tx_timeout);
+
+static ssize_t current_rssi_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", s->current_rssi);
+}
+
+/*
+ * current_rssi: ro sysfs entry.
+ * Returns the latest rssi value measured by chip.
+ */
+static DEVICE_ATTR_RO(current_rssi);
+
+static struct attribute *si4455_attributes[] = {
+ &dev_attr_package_size.attr,
+ &dev_attr_rx_channel.attr,
+ &dev_attr_tx_channel.attr,
+ &dev_attr_tx_timeout.attr,
+ &dev_attr_current_rssi.attr,
+ NULL
+};
+
+static const struct attribute_group si4455_attr_group = {
+ .attrs = si4455_attributes,
+};
+
+static int si4455_probe(struct device *dev,
+ int irq)
+{
+ int ret;
+ struct si4455_port *s;
+ const void *of_ptr;
+ const struct firmware *ez_fw = NULL;
+ int line;
+
+ /* Alloc port structure */
+ s = devm_kzalloc(dev, sizeof(*s), GFP_KERNEL);
+ if (!s)
+ return -ENOMEM;
+
+ dev_set_drvdata(dev, s);
+ mutex_init(&s->mutex);
+
+ /* Alloc port line */
+ line = find_first_zero_bit(si4455_port_lines, SI4455_UART_NRMAX);
+ if (line == SI4455_UART_NRMAX) {
+ dev_err(dev, "Unable to reguest port line index\n");
+ ret = -ERANGE;
+ goto out_generic;
+ }
+
+ s->shdn_gpio = devm_gpiod_get(dev, "shutdown", GPIOD_OUT_HIGH);
+ if (IS_ERR(s->shdn_gpio)) {
+ dev_err(dev, "Unable to reguest shdn gpio\n");
+ ret = -EINVAL;
+ goto out_generic;
+ }
+
+ of_ptr = of_get_property(dev->of_node, "silabs,package-size", NULL);
+ if (IS_ERR_OR_NULL(of_ptr)) {
+ dev_err(dev, "dt silabs,package-size property not present\n");
+ ret = -EINVAL;
+ goto out_generic;
+ }
+ s->package_size = be32_to_cpup(of_ptr);
+ if (s->package_size > SI4455_FIFO_SIZE) {
+ dev_err(dev, "dt silabs,package-size property maximum is %i\n", SI4455_FIFO_SIZE);
+ ret = -EINVAL;
+ goto out_generic;
+ }
+
+ of_ptr = of_get_property(dev->of_node, "silabs,tx-channel", NULL);
+ if (IS_ERR_OR_NULL(of_ptr)) {
+ dev_err(dev, "dt silabs,tx-channel property not present\n");
+ ret = -EINVAL;
+ goto out_generic;
+ }
+ s->tx_channel = be32_to_cpup(of_ptr);
+
+ of_ptr = of_get_property(dev->of_node, "silabs,rx-channel", NULL);
+ if (IS_ERR_OR_NULL(of_ptr)) {
+ dev_err(dev, "dt silabs,rx-channel property not present\n");
+ ret = -EINVAL;
+ goto out_generic;
+ }
+ s->rx_channel = be32_to_cpup(of_ptr);
+
+ of_ptr = of_get_property(dev->of_node, "silabs,tx-timeout-ms", NULL);
+ if (IS_ERR_OR_NULL(of_ptr)) {
+ s->tx_wd_timeout = 100;
+ dev_warn(dev, "dt silabs,tx-timeout-ms property not present\n");
+ } else {
+ s->tx_wd_timeout = be32_to_cpup(of_ptr);
+ }
+
+ of_ptr = of_get_property(dev->of_node, "firmware-name", NULL);
+ if (IS_ERR_OR_NULL(of_ptr)) {
+ dev_err(dev, "dt firmware-name property not present\n");
+ ret = -EINVAL;
+ goto out_generic;
+ }
+ strncpy(s->ez_fw_name, of_ptr, sizeof(s->ez_fw_name) - 1);
+
+ /* Initialize port data */
+ s->port.dev = dev;
+ s->port.line = line;
+ s->port.irq = irq;
+ s->port.type = PORT_SI4455;
+ s->port.fifosize = SI4455_FIFO_SIZE;
+ s->port.flags = UPF_FIXED_TYPE | UPF_LOW_LATENCY;
+ s->port.iotype = UPIO_PORT;
+ s->port.iobase = 1;
+ s->port.ops = &si4455_ops;
+
+ si4455_s_power(dev, true);
+
+ ret = si4455_get_part_info(&s->port, &s->part_info);
+ dev_dbg(dev, "si4455_get_part_info() = %i\n", ret);
+ if (ret == 0) {
+ dev_info(dev, "partInfo.chip_rev = %u\n", s->part_info.chip_rev);
+ dev_info(dev, "partInfo.part = %u\n", s->part_info.part);
+ dev_info(dev, "partInfo.pbuild = %u\n", s->part_info.pbuild);
+ dev_info(dev, "partInfo.id = %u\n", s->part_info.id);
+ dev_info(dev, "partInfo.customer = %u\n", s->part_info.customer);
+ dev_info(dev, "partInfo.rom_id = %u\n", s->part_info.rom_id);
+ dev_info(dev, "partInfo.bond = %u\n", s->part_info.bond);
+ if (s->part_info.part != 0x5544) {
+ dev_err(dev, "unknown part(%u) error\n", s->part_info.part);
+ ret = -ENODEV;
+ }
+ }
+
+ if (ret)
+ goto out_generic;
+
+ ret = request_firmware(&ez_fw, s->ez_fw_name, dev);
+ if (ret) {
+ dev_err(dev, "firmware(%s) request error (%i)\n", s->ez_fw_name, ret);
+ ret = -EINVAL;
+ goto out_generic;
+ }
+
+ ret = si4455_re_configure(&s->port, ez_fw);
+ release_firmware(ez_fw);
+ if (ret) {
+ dev_err(dev, "device configuration error (%i)\n", ret);
+ ret = -EINVAL;
+ goto out_generic;
+ }
+
+ ret = si4455_change_state(&s->port, SI4455_CMD_CHANGE_STATE_STATE_SLEEP);
+ if (ret) {
+ dev_err(dev, "device change state error (%i)\n", ret);
+ goto out_generic;
+ }
+
+ /* Initialize queue for start TX */
+ INIT_WORK(&s->tx_work, si4455_tx_proc);
+ /* Initialize queue for start TX watchdog */
+ INIT_WORK(&s->tx_wd_work, si4455_tx_wd_proc);
+ /* Initialize queue for cts watchdog */
+ INIT_WORK(&s->cts_wd_work, si4455_cts_wd_proc);
+ /* Initialize timer for protecting and recovering tx_pending */
+ timer_setup(&s->tx_wd_timer, si4455_tx_wd_event, 0);
+ /* Initialize timer for recovering interface */
+ timer_setup(&s->cts_wd_timer, si4455_cts_wd_event, 0);
+
+ /* Register port */
+ ret = uart_add_one_port(&si4455_uart, &s->port);
+ if (ret) {
+ s->port.dev = NULL;
+ goto out_uart;
+ }
+
+ set_bit(line, si4455_port_lines);
+ s->port.line = line;
+
+ ret = sysfs_create_group(&dev->kobj, &si4455_attr_group);
+ if (ret) {
+ dev_err(dev, "sysfs_create_group error (%i)\n", ret);
+ goto out_uart;
+ }
+
+ si4455_debugfs_init(dev);
+
+ /* Setup interrupt */
+ ret = devm_request_threaded_irq(dev, irq, NULL, si4455_ist,
+ IRQF_ONESHOT | IRQF_SHARED,
+ dev_name(dev), s);
+ if (!ret)
+ return 0;
+
+ dev_err(dev, "Unable to reguest IRQ %i\n", irq);
+ sysfs_remove_group(&dev->kobj, &si4455_attr_group);
+
+out_uart:
+ uart_remove_one_port(&si4455_uart, &s->port);
+ clear_bit(line, si4455_port_lines);
+out_generic:
+ mutex_destroy(&s->mutex);
+ si4455_s_power(dev, false);
+
+ return ret;
+}
+
+static int si4455_remove(struct device *dev)
+{
+ struct si4455_port *s = dev_get_drvdata(dev);
+ int line = s->port.line;
+
+ cancel_work_sync(&s->tx_work);
+ sysfs_remove_group(&dev->kobj, &si4455_attr_group);
+ si4455_debugfs_clear(dev);
+ uart_remove_one_port(&si4455_uart, &s->port);
+ mutex_destroy(&s->mutex);
+ clear_bit(line, si4455_port_lines);
+
+ return 0;
+}
+
+static const struct of_device_id __maybe_unused si4455_dt_ids[] = {
+ { .compatible = "silabs,si4455" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, si4455_dt_ids);
+
+static int si4455_spi_probe(struct spi_device *spi)
+{
+ int ret;
+ const struct of_device_id *of_id;
+
+ /* Setup SPI bus */
+ spi->bits_per_word = 8;
+ spi->mode = SPI_MODE_0;
+ ret = spi_setup(spi);
+ if (ret)
+ return ret;
+
+ if (spi->dev.of_node) {
+ of_id = of_match_device(si4455_dt_ids, &spi->dev);
+ if (!of_id)
+ return -ENODEV;
+ }
+
+ mutex_lock(&si4455_ports_lock);
+ ret = si4455_probe(&spi->dev, spi->irq);
+ mutex_unlock(&si4455_ports_lock);
+ return ret;
+}
+
+static int si4455_spi_remove(struct spi_device *spi)
+{
+ int ret;
+
+ mutex_lock(&si4455_ports_lock);
+ ret = si4455_remove(&spi->dev);
+ mutex_unlock(&si4455_ports_lock);
+ return ret;
+}
+
+static struct spi_driver si4455_spi_driver = {
+ .driver = {
+ .name = SI4455_NAME,
+ .of_match_table = of_match_ptr(si4455_dt_ids),
+ .pm = &si4455_pm_ops,
+ },
+ .probe = si4455_spi_probe,
+ .remove = si4455_spi_remove,
+};
+
+static int __init si4455_uart_init(void)
+{
+ int ret;
+
+ bitmap_zero(si4455_port_lines, SI4455_UART_NRMAX);
+
+ ret = uart_register_driver(&si4455_uart);
+ if (ret)
+ return ret;
+
+ return spi_register_driver(&si4455_spi_driver);
+}
+module_init(si4455_uart_init);
+
+static void __exit si4455_uart_exit(void)
+{
+ spi_unregister_driver(&si4455_spi_driver);
+ uart_unregister_driver(&si4455_uart);
+}
+module_exit(si4455_uart_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jozsef Horvath <info@ministro.hu>");
+MODULE_DESCRIPTION("Si4455 serial driver");
diff --git a/include/uapi/linux/serial_core.h b/include/uapi/linux/serial_core.h
index 851b982f8c4b..943c5e2e27fc 100644
--- a/include/uapi/linux/serial_core.h
+++ b/include/uapi/linux/serial_core.h
@@ -279,4 +279,7 @@
/* Freescale LINFlexD UART */
#define PORT_LINFLEXUART 122

+/* Silicon Labs SI4455 */
+#define PORT_SI4455 123
+
#endif /* _UAPILINUX_SERIAL_CORE_H */
--
2.17.1