diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-xgene-slimpro.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-xgene-slimpro.c | 470 |
1 files changed, 470 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-xgene-slimpro.c b/drivers/i2c/busses/i2c-xgene-slimpro.c new file mode 100644 index 000000000..1c9cb65ac --- /dev/null +++ b/drivers/i2c/busses/i2c-xgene-slimpro.c @@ -0,0 +1,470 @@ +/* + * X-Gene SLIMpro I2C Driver + * + * Copyright (c) 2014, Applied Micro Circuits Corporation + * Author: Feng Kan <fkan@apm.com> + * Author: Hieu Le <hnle@apm.com> + * + * 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 should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + * + * This driver provides support for X-Gene SLIMpro I2C device access + * using the APM X-Gene SLIMpro mailbox driver. + * + */ +#include <linux/acpi.h> +#include <linux/dma-mapping.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/mailbox_client.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/version.h> + +#define MAILBOX_OP_TIMEOUT 1000 /* Operation time out in ms */ +#define MAILBOX_I2C_INDEX 0 +#define SLIMPRO_IIC_BUS 1 /* Use I2C bus 1 only */ + +#define SMBUS_CMD_LEN 1 +#define BYTE_DATA 1 +#define WORD_DATA 2 +#define BLOCK_DATA 3 + +#define SLIMPRO_IIC_I2C_PROTOCOL 0 +#define SLIMPRO_IIC_SMB_PROTOCOL 1 + +#define SLIMPRO_IIC_READ 0 +#define SLIMPRO_IIC_WRITE 1 + +#define IIC_SMB_WITHOUT_DATA_LEN 0 +#define IIC_SMB_WITH_DATA_LEN 1 + +#define SLIMPRO_DEBUG_MSG 0 +#define SLIMPRO_MSG_TYPE_SHIFT 28 +#define SLIMPRO_DBG_SUBTYPE_I2C1READ 4 +#define SLIMPRO_DBGMSG_TYPE_SHIFT 24 +#define SLIMPRO_DBGMSG_TYPE_MASK 0x0F000000U +#define SLIMPRO_IIC_DEV_SHIFT 23 +#define SLIMPRO_IIC_DEV_MASK 0x00800000U +#define SLIMPRO_IIC_DEVID_SHIFT 13 +#define SLIMPRO_IIC_DEVID_MASK 0x007FE000U +#define SLIMPRO_IIC_RW_SHIFT 12 +#define SLIMPRO_IIC_RW_MASK 0x00001000U +#define SLIMPRO_IIC_PROTO_SHIFT 11 +#define SLIMPRO_IIC_PROTO_MASK 0x00000800U +#define SLIMPRO_IIC_ADDRLEN_SHIFT 8 +#define SLIMPRO_IIC_ADDRLEN_MASK 0x00000700U +#define SLIMPRO_IIC_DATALEN_SHIFT 0 +#define SLIMPRO_IIC_DATALEN_MASK 0x000000FFU + +/* + * SLIMpro I2C message encode + * + * dev - Controller number (0-based) + * chip - I2C chip address + * op - SLIMPRO_IIC_READ or SLIMPRO_IIC_WRITE + * proto - SLIMPRO_IIC_SMB_PROTOCOL or SLIMPRO_IIC_I2C_PROTOCOL + * addrlen - Length of the address field + * datalen - Length of the data field + */ +#define SLIMPRO_IIC_ENCODE_MSG(dev, chip, op, proto, addrlen, datalen) \ + ((SLIMPRO_DEBUG_MSG << SLIMPRO_MSG_TYPE_SHIFT) | \ + ((SLIMPRO_DBG_SUBTYPE_I2C1READ << SLIMPRO_DBGMSG_TYPE_SHIFT) & \ + SLIMPRO_DBGMSG_TYPE_MASK) | \ + ((dev << SLIMPRO_IIC_DEV_SHIFT) & SLIMPRO_IIC_DEV_MASK) | \ + ((chip << SLIMPRO_IIC_DEVID_SHIFT) & SLIMPRO_IIC_DEVID_MASK) | \ + ((op << SLIMPRO_IIC_RW_SHIFT) & SLIMPRO_IIC_RW_MASK) | \ + ((proto << SLIMPRO_IIC_PROTO_SHIFT) & SLIMPRO_IIC_PROTO_MASK) | \ + ((addrlen << SLIMPRO_IIC_ADDRLEN_SHIFT) & SLIMPRO_IIC_ADDRLEN_MASK) | \ + ((datalen << SLIMPRO_IIC_DATALEN_SHIFT) & SLIMPRO_IIC_DATALEN_MASK)) + +/* + * Encode for upper address for block data + */ +#define SLIMPRO_IIC_ENCODE_FLAG_BUFADDR 0x80000000 +#define SLIMPRO_IIC_ENCODE_FLAG_WITH_DATA_LEN(a) ((u32) (((a) << 30) \ + & 0x40000000)) +#define SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(a) ((u32) (((a) >> 12) \ + & 0x3FF00000)) +#define SLIMPRO_IIC_ENCODE_ADDR(a) ((a) & 0x000FFFFF) + +struct slimpro_i2c_dev { + struct i2c_adapter adapter; + struct device *dev; + struct mbox_chan *mbox_chan; + struct mbox_client mbox_client; + struct completion rd_complete; + u8 dma_buffer[I2C_SMBUS_BLOCK_MAX]; + u32 *resp_msg; +}; + +#define to_slimpro_i2c_dev(cl) \ + container_of(cl, struct slimpro_i2c_dev, mbox_client) + +static void slimpro_i2c_rx_cb(struct mbox_client *cl, void *mssg) +{ + struct slimpro_i2c_dev *ctx = to_slimpro_i2c_dev(cl); + + /* + * Response message format: + * mssg[0] is the return code of the operation + * mssg[1] is the first data word + * mssg[2] is NOT used + */ + if (ctx->resp_msg) + *ctx->resp_msg = ((u32 *)mssg)[1]; + + if (ctx->mbox_client.tx_block) + complete(&ctx->rd_complete); +} + +static int start_i2c_msg_xfer(struct slimpro_i2c_dev *ctx) +{ + if (ctx->mbox_client.tx_block) { + if (!wait_for_completion_timeout(&ctx->rd_complete, + msecs_to_jiffies(MAILBOX_OP_TIMEOUT))) + return -ETIMEDOUT; + } + + /* Check of invalid data or no device */ + if (*ctx->resp_msg == 0xffffffff) + return -ENODEV; + + return 0; +} + +static int slimpro_i2c_rd(struct slimpro_i2c_dev *ctx, u32 chip, + u32 addr, u32 addrlen, u32 protocol, + u32 readlen, u32 *data) +{ + u32 msg[3]; + int rc; + + msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, + SLIMPRO_IIC_READ, protocol, addrlen, readlen); + msg[1] = SLIMPRO_IIC_ENCODE_ADDR(addr); + msg[2] = 0; + ctx->resp_msg = data; + rc = mbox_send_message(ctx->mbox_chan, &msg); + if (rc < 0) + goto err; + + rc = start_i2c_msg_xfer(ctx); +err: + ctx->resp_msg = NULL; + return rc; +} + +static int slimpro_i2c_wr(struct slimpro_i2c_dev *ctx, u32 chip, + u32 addr, u32 addrlen, u32 protocol, u32 writelen, + u32 data) +{ + u32 msg[3]; + int rc; + + msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, + SLIMPRO_IIC_WRITE, protocol, addrlen, writelen); + msg[1] = SLIMPRO_IIC_ENCODE_ADDR(addr); + msg[2] = data; + ctx->resp_msg = msg; + + rc = mbox_send_message(ctx->mbox_chan, &msg); + if (rc < 0) + goto err; + + rc = start_i2c_msg_xfer(ctx); +err: + ctx->resp_msg = NULL; + return rc; +} + +static int slimpro_i2c_blkrd(struct slimpro_i2c_dev *ctx, u32 chip, u32 addr, + u32 addrlen, u32 protocol, u32 readlen, + u32 with_data_len, void *data) +{ + dma_addr_t paddr; + u32 msg[3]; + int rc; + + paddr = dma_map_single(ctx->dev, ctx->dma_buffer, readlen, DMA_FROM_DEVICE); + rc = dma_mapping_error(ctx->dev, paddr); + if (rc) { + dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n", + ctx->dma_buffer); + goto err; + } + + msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_READ, + protocol, addrlen, readlen); + msg[1] = SLIMPRO_IIC_ENCODE_FLAG_BUFADDR | + SLIMPRO_IIC_ENCODE_FLAG_WITH_DATA_LEN(with_data_len) | + SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(paddr) | + SLIMPRO_IIC_ENCODE_ADDR(addr); + msg[2] = (u32)paddr; + ctx->resp_msg = msg; + + rc = mbox_send_message(ctx->mbox_chan, &msg); + if (rc < 0) + goto err_unmap; + + rc = start_i2c_msg_xfer(ctx); + + /* Copy to destination */ + memcpy(data, ctx->dma_buffer, readlen); + +err_unmap: + dma_unmap_single(ctx->dev, paddr, readlen, DMA_FROM_DEVICE); +err: + ctx->resp_msg = NULL; + return rc; +} + +static int slimpro_i2c_blkwr(struct slimpro_i2c_dev *ctx, u32 chip, + u32 addr, u32 addrlen, u32 protocol, u32 writelen, + void *data) +{ + dma_addr_t paddr; + u32 msg[3]; + int rc; + + memcpy(ctx->dma_buffer, data, writelen); + paddr = dma_map_single(ctx->dev, ctx->dma_buffer, writelen, + DMA_TO_DEVICE); + rc = dma_mapping_error(ctx->dev, paddr); + if (rc) { + dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n", + ctx->dma_buffer); + goto err; + } + + msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_WRITE, + protocol, addrlen, writelen); + msg[1] = SLIMPRO_IIC_ENCODE_FLAG_BUFADDR | + SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(paddr) | + SLIMPRO_IIC_ENCODE_ADDR(addr); + msg[2] = (u32)paddr; + ctx->resp_msg = msg; + + if (ctx->mbox_client.tx_block) + reinit_completion(&ctx->rd_complete); + + rc = mbox_send_message(ctx->mbox_chan, &msg); + if (rc < 0) + goto err_unmap; + + rc = start_i2c_msg_xfer(ctx); + +err_unmap: + dma_unmap_single(ctx->dev, paddr, writelen, DMA_TO_DEVICE); +err: + ctx->resp_msg = NULL; + return rc; +} + +static int xgene_slimpro_i2c_xfer(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + struct slimpro_i2c_dev *ctx = i2c_get_adapdata(adap); + int ret = -EOPNOTSUPP; + u32 val; + + switch (size) { + case I2C_SMBUS_BYTE: + if (read_write == I2C_SMBUS_READ) { + ret = slimpro_i2c_rd(ctx, addr, 0, 0, + SLIMPRO_IIC_SMB_PROTOCOL, + BYTE_DATA, &val); + data->byte = val; + } else { + ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + 0, 0); + } + break; + case I2C_SMBUS_BYTE_DATA: + if (read_write == I2C_SMBUS_READ) { + ret = slimpro_i2c_rd(ctx, addr, command, SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + BYTE_DATA, &val); + data->byte = val; + } else { + val = data->byte; + ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + BYTE_DATA, val); + } + break; + case I2C_SMBUS_WORD_DATA: + if (read_write == I2C_SMBUS_READ) { + ret = slimpro_i2c_rd(ctx, addr, command, SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + WORD_DATA, &val); + data->word = val; + } else { + val = data->word; + ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + WORD_DATA, val); + } + break; + case I2C_SMBUS_BLOCK_DATA: + if (read_write == I2C_SMBUS_READ) { + ret = slimpro_i2c_blkrd(ctx, addr, command, + SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + I2C_SMBUS_BLOCK_MAX + 1, + IIC_SMB_WITH_DATA_LEN, + &data->block[0]); + + } else { + ret = slimpro_i2c_blkwr(ctx, addr, command, + SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + data->block[0] + 1, + &data->block[0]); + } + break; + case I2C_SMBUS_I2C_BLOCK_DATA: + if (read_write == I2C_SMBUS_READ) { + ret = slimpro_i2c_blkrd(ctx, addr, + command, + SMBUS_CMD_LEN, + SLIMPRO_IIC_I2C_PROTOCOL, + I2C_SMBUS_BLOCK_MAX, + IIC_SMB_WITHOUT_DATA_LEN, + &data->block[1]); + } else { + ret = slimpro_i2c_blkwr(ctx, addr, command, + SMBUS_CMD_LEN, + SLIMPRO_IIC_I2C_PROTOCOL, + data->block[0], + &data->block[1]); + } + break; + default: + break; + } + return ret; +} + +/* +* Return list of supported functionality. +*/ +static u32 xgene_slimpro_i2c_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_BLOCK_DATA | + I2C_FUNC_SMBUS_I2C_BLOCK; +} + +static struct i2c_algorithm xgene_slimpro_i2c_algorithm = { + .smbus_xfer = xgene_slimpro_i2c_xfer, + .functionality = xgene_slimpro_i2c_func, +}; + +static int xgene_slimpro_i2c_probe(struct platform_device *pdev) +{ + struct slimpro_i2c_dev *ctx; + struct i2c_adapter *adapter; + struct mbox_client *cl; + int rc; + + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + ctx->dev = &pdev->dev; + platform_set_drvdata(pdev, ctx); + cl = &ctx->mbox_client; + + /* Request mailbox channel */ + cl->dev = &pdev->dev; + cl->rx_callback = slimpro_i2c_rx_cb; + cl->tx_block = true; + init_completion(&ctx->rd_complete); + cl->tx_tout = MAILBOX_OP_TIMEOUT; + cl->knows_txdone = false; + ctx->mbox_chan = mbox_request_channel(cl, MAILBOX_I2C_INDEX); + if (IS_ERR(ctx->mbox_chan)) { + dev_err(&pdev->dev, "i2c mailbox channel request failed\n"); + return PTR_ERR(ctx->mbox_chan); + } + + rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); + if (rc) + dev_warn(&pdev->dev, "Unable to set dma mask\n"); + + /* Setup I2C adapter */ + adapter = &ctx->adapter; + snprintf(adapter->name, sizeof(adapter->name), "MAILBOX I2C"); + adapter->algo = &xgene_slimpro_i2c_algorithm; + adapter->class = I2C_CLASS_HWMON; + adapter->dev.parent = &pdev->dev; + i2c_set_adapdata(adapter, ctx); + rc = i2c_add_adapter(adapter); + if (rc) { + dev_err(&pdev->dev, "Adapter registeration failed\n"); + mbox_free_channel(ctx->mbox_chan); + return rc; + } + + dev_info(&pdev->dev, "Mailbox I2C Adapter registered\n"); + return 0; +} + +static int xgene_slimpro_i2c_remove(struct platform_device *pdev) +{ + struct slimpro_i2c_dev *ctx = platform_get_drvdata(pdev); + + i2c_del_adapter(&ctx->adapter); + + mbox_free_channel(ctx->mbox_chan); + + return 0; +} + +static const struct of_device_id xgene_slimpro_i2c_dt_ids[] = { + {.compatible = "apm,xgene-slimpro-i2c" }, + {}, +}; +MODULE_DEVICE_TABLE(of, xgene_slimpro_i2c_dt_ids); + +#ifdef CONFIG_ACPI +static const struct acpi_device_id xgene_slimpro_i2c_acpi_ids[] = { + {"APMC0D40", 0}, + {} +}; +MODULE_DEVICE_TABLE(acpi, xgene_slimpro_i2c_acpi_ids); +#endif + +static struct platform_driver xgene_slimpro_i2c_driver = { + .probe = xgene_slimpro_i2c_probe, + .remove = xgene_slimpro_i2c_remove, + .driver = { + .name = "xgene-slimpro-i2c", + .of_match_table = of_match_ptr(xgene_slimpro_i2c_dt_ids), + .acpi_match_table = ACPI_PTR(xgene_slimpro_i2c_acpi_ids) + }, +}; + +module_platform_driver(xgene_slimpro_i2c_driver); + +MODULE_DESCRIPTION("APM X-Gene SLIMpro I2C driver"); +MODULE_AUTHOR("Feng Kan <fkan@apm.com>"); +MODULE_AUTHOR("Hieu Le <hnle@apm.com>"); +MODULE_LICENSE("GPL"); |