diff options
Diffstat (limited to 'driver')
| -rw-r--r-- | driver/build.mk | 3 | ||||
| -rw-r--r-- | driver/mcdp28x0.c | 149 | ||||
| -rw-r--r-- | driver/mcdp28x0.h | 56 |
3 files changed, 208 insertions, 0 deletions
diff --git a/driver/build.mk b/driver/build.mk index 2d5de551a8..923be6ac1a 100644 --- a/driver/build.mk +++ b/driver/build.mk @@ -53,3 +53,6 @@ driver-$(CONFIG_USB_SWITCH_TSU6721)+=usb_switch_tsu6721.o # Firmware Update driver-$(CONFIG_SB_FIRMWARE_UPDATE)+=battery/sb_fw_update.o + +# video converters +driver-$(CONFIG_MCDP28X0)+=mcdp28x0.o diff --git a/driver/mcdp28x0.c b/driver/mcdp28x0.c new file mode 100644 index 0000000000..de334b5c59 --- /dev/null +++ b/driver/mcdp28x0.c @@ -0,0 +1,149 @@ +/* Copyright (c) 2014 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + * + * Megachips DisplayPort to HDMI protocol converter / level shifter driver. + */ + +#include "config.h" +#include "console.h" +#include "common.h" +#include "mcdp28x0.h" +#include "timer.h" +#include "usart-stm32f0.h" +#include "util.h" + +#define CPRINTF(format, args...) cprintf(CC_USBPD, format, ## args) + +#undef MCDP_DEBUG + +#ifdef MCDP_DEBUG +static inline void print_buffer(uint8_t *buf, int cnt) +{ + int i; + CPRINTF("buf:"); + for (i = 0; i < cnt; i++) { + if (i && !(i % 4)) + CPRINTF("\n "); + CPRINTF("[%02d]0x%02x ", i, buf[i]); + } + CPRINTF("\n"); +} +#else +static inline void print_buffer(uint8_t *buf, int cnt) {} +#endif + +USART_CONFIG(usart_mcdp, CONFIG_MCDP28X0, 115200, MCDP_INBUF_MAX, + MCDP_OUTBUF_MAX, NULL, NULL); + +/** + * Compute checksum. + * + * @msg message bytes to compute checksum on. + * @cnt count of message bytes. + * @return partial checksum. + */ +static uint8_t compute_checksum(const uint8_t *msg, int cnt) +{ + int i; + /* 1st byte (not in msg) is always cnt + 2, so seed chksum with that */ + uint8_t chksum = cnt + 2; + + for (i = 0; i < cnt; i++) + chksum += msg[i]; + return ~chksum + 1; +} + +/** + * transmit message over serial + * + * Packet consists of: + * msg[0] == length including this byte + cnt + chksum + * msg[1] == 1st message byte + * msg[cnt+1] == last message byte + * msg[cnt+2] == checksum + * + * @msg message bytes + * @cnt count of message bytes + * @return zero if success, error code otherwise + */ +static int tx_serial(const uint8_t *msg, int cnt) +{ + uint8_t out = cnt + 2; + uint8_t chksum = compute_checksum(msg, cnt); + + if (out_stream_write(&usart_mcdp.out, &out, 1) != 1) + return EC_ERROR_UNKNOWN; + + if (out_stream_write(&usart_mcdp.out, msg, cnt) != cnt) + return EC_ERROR_UNKNOWN; + + if (out_stream_write(&usart_mcdp.out, &chksum, 1) != 1) + return EC_ERROR_UNKNOWN; + + print_buffer(usart_mcdp_tx_buffer, cnt + 2); + + return EC_SUCCESS; +} + +/** + * receive message over serial + * + * @msg pointer to buffer to read message into + * @cnt count of message bytes + * @return zero if success, error code otherwise + */ +static int rx_serial(uint8_t *msg, int cnt) +{ + size_t read; + int retry = 2; + + read = in_stream_read(&usart_mcdp.in, msg, cnt); + while ((read < cnt) && retry) { + usleep(100*MSEC); + read += in_stream_read(&usart_mcdp.in, msg + read, + cnt - read); + retry--; + } + + print_buffer(msg, cnt); + + return !(read == cnt); +} + +void mcdp_enable(void) +{ + usart_init(&usart_mcdp); +} + +void mcdp_disable(void) +{ + usart_shutdown(&usart_mcdp); +} + +int mcdp_get_info(struct mcdp_info *info) +{ + uint8_t inbuf[MCDP_RSP_LEN(MCDP_LEN_GETINFO)]; + const uint8_t msg[2] = {MCDP_CMD_GETINFO, 0x00}; /* cmd + msg type */ + + if (tx_serial(msg, sizeof(msg))) + return EC_ERROR_UNKNOWN; + + if (rx_serial(inbuf, sizeof(inbuf))) + return EC_ERROR_UNKNOWN; + + /* check length & returned command ... no checksum provided */ + if (((inbuf[0] - 1) != sizeof(inbuf)) || + (inbuf[1] != MCDP_CMD_GETINFO)) + return EC_ERROR_UNKNOWN; + + memcpy(info, &inbuf[2], MCDP_LEN_GETINFO); + +#ifdef MCDP_DEBUG + CPRINTF("family:%04x chipid:%04x irom:%d.%d.%d fw:%d.%d.%d\n", + MCDP_FAMILY(info->family), MCDP_CHIPID(info->chipid), + info->irom.major, info->irom.minor, info->irom.build, + info->fw.major, info->fw.minor, info->fw.build); +#endif + return EC_SUCCESS; +} diff --git a/driver/mcdp28x0.h b/driver/mcdp28x0.h new file mode 100644 index 0000000000..c753816495 --- /dev/null +++ b/driver/mcdp28x0.h @@ -0,0 +1,56 @@ +/* Copyright (c) 2014 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + * + * Megachips DisplayPort to HDMI protocol converter / level shifter driver. + */ + +#ifndef MCDP28X0_H +#define MCDP28X0_H + +#include <util.h> + +#define MCDP_OUTBUF_MAX 16 +#define MCDP_INBUF_MAX 16 + +#define MCDP_CHIPID(chipid) ((chipid[0] << 8) | chipid[1]) +#define MCDP_FAMILY(family) ((family[0] << 8) | family[1]) + +#define MCDP_CMD_GETINFO 0x40 +#define MCDP_LEN_GETINFO 12 + +/* length byte + cmd byte + data len */ +#define MCDP_RSP_LEN(len) (len + 2) + +struct mcdp_version { + uint8_t major; + uint8_t minor; + uint16_t build; +}; + +struct mcdp_info { + uint8_t family[2]; + uint8_t chipid[2]; + struct mcdp_version irom; + struct mcdp_version fw; +}; + +/** + * Enable mcdp driver. + */ +void mcdp_enable(void); + +/** + * Disable mcdp driver. + */ +void mcdp_disable(void); + +/** + * get get information command from mcdp. + * + * @info pointer to mcdp_info structure + * @return zero if success, error code otherwise. + */ +int mcdp_get_info(struct mcdp_info *info); + +#endif |