Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966093AbbKEXlw (ORCPT ); Thu, 5 Nov 2015 18:41:52 -0500 Received: from us-mx2.synaptics.com ([192.147.44.131]:63087 "EHLO us-mx1.synaptics.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S965935AbbKEXls (ORCPT ); Thu, 5 Nov 2015 18:41:48 -0500 X-PGP-Universal: processed; by securemail.synaptics.com on Thu, 05 Nov 2015 16:42:11 -0800 From: Andrew Duggan To: , CC: Andrew Duggan , Dmitry Torokhov , Linus Walleij , Benjamin Tissoires , Christopher Heiny , Stephen Chandler Paul Subject: [PATCH 18/26] Input: synaptics-rmi4: Add SPI transport driver Date: Thu, 5 Nov 2015 15:41:40 -0800 Message-ID: <1446766900-31032-1-git-send-email-aduggan@synaptics.com> X-Mailer: git-send-email 2.1.4 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.4.10.145] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 15433 Lines: 598 Add a transport driver for devices using RMI4 over SPI. Signed-off-by: Andrew Duggan --- .../devicetree/bindings/input/rmi4/rmi_spi.txt | 57 +++ drivers/input/rmi4/Kconfig | 9 + drivers/input/rmi4/Makefile | 1 + drivers/input/rmi4/rmi_spi.c | 464 +++++++++++++++++++++ include/linux/rmi.h | 2 + 5 files changed, 533 insertions(+) create mode 100644 Documentation/devicetree/bindings/input/rmi4/rmi_spi.txt create mode 100644 drivers/input/rmi4/rmi_spi.c diff --git a/Documentation/devicetree/bindings/input/rmi4/rmi_spi.txt b/Documentation/devicetree/bindings/input/rmi4/rmi_spi.txt new file mode 100644 index 0000000..f20366b6 --- /dev/null +++ b/Documentation/devicetree/bindings/input/rmi4/rmi_spi.txt @@ -0,0 +1,57 @@ +Synaptics RMI4 SPI Device Binding + +The Synaptics RMI4 core is able to support RMI4 devices using differnet +transports and differnet functions. This file describes the device tree +bindings for devices using the SPI tranport driver. Complete documentation +for other transports and functions cen be found ini +Documentation/devicetree/bindings/input/rmi4. + +Required Properties: +- compatible: syna,rmi-spi +- reg: Chip select address for the device +- #address-cells: Set to 1 to indicate that the function child nodes + consist of only on uint32 value. +- #size-cells: Set to 0 to indicate that the function child nodes do not + have a size property. + +Optional Properties: +- interrupts: interrupt which the rmi device is connected to. +- interrupt-parent: The interrupt controller. +See Documentation/devicetree/bindings/interrupt-controller/interrupts.txt + +- syna,spi-read-delay: millisecond delay between read byte transfers. +- syna,spi-write-delay: millisecond delay between write byte transfers. + +Function Parameters: +Parameters specific to RMI functions are contained in child nodes of the rmi device + node. Documentation for the parameters of each function can be found in: +Documentation/devicetree/bindings/input/rmi4/rmi_f*.txt. + + + +Example: + spi@7000d800 { + rmi-spi-dev@0 { + compatible = "syna,rmi-spi"; + reg = <0x0>; + #address-cells = <1>; + #size-cells = <0>; + spi-max-frequency = <4000000>; + spi-cpha; + spi-cpol; + interrupt-parent = <&gpio>; + interrupts = ; + syna,spi-read-delay = <30>; + + rmi-f01@1 { + reg = <0x1>; + syna,nosleep-mode = <1>; + }; + + rmi-f11@11 { + reg = <0x11>; + syna,flip-y; + syna,sensor-type = <2>; + }; + }; + }; diff --git a/drivers/input/rmi4/Kconfig b/drivers/input/rmi4/Kconfig index 5e3890e..88a3919 100644 --- a/drivers/input/rmi4/Kconfig +++ b/drivers/input/rmi4/Kconfig @@ -36,6 +36,15 @@ config RMI4_I2C This feature is not currently available as a loadable module. +config RMI4_SPI + tristate "RMI4 SPI Support" + depends on RMI4_CORE && SPI + help + Say Y here if you want to support RMI4 devices connected to a SPI + bus. + + If unsure, say N. + config RMI4_F11 bool "RMI4 Function 11 (2D pointing)" depends on RMI4_CORE diff --git a/drivers/input/rmi4/Makefile b/drivers/input/rmi4/Makefile index 37b6789..1745757 100644 --- a/drivers/input/rmi4/Makefile +++ b/drivers/input/rmi4/Makefile @@ -6,5 +6,6 @@ rmi_core-$(CONFIG_RMI4_F11) += rmi_f11.o # Transports obj-$(CONFIG_RMI4_I2C) += rmi_i2c.o +obj-$(CONFIG_RMI4_SPI) += rmi_spi.o ccflags-$(CONFIG_RMI4_DEBUG) += -DDEBUG diff --git a/drivers/input/rmi4/rmi_spi.c b/drivers/input/rmi4/rmi_spi.c new file mode 100644 index 0000000..1b6c258 --- /dev/null +++ b/drivers/input/rmi4/rmi_spi.c @@ -0,0 +1,464 @@ +/* + * Copyright (c) 2011, 2012 Synaptics Incorporated + * Copyright (c) 2011 Unixphere + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + */ + +#include +#include +#include +#include +#include +#include +#include "rmi_driver.h" + +#define RMI_SPI_DEFAULT_XFER_BUF_SIZE 64 + +#define RMI_PAGE_SELECT_REGISTER 0x00FF +#define RMI_SPI_PAGE(addr) (((addr) >> 8) & 0x80) +#define RMI_SPI_XFER_SIZE_LIMIT 255 + +#define BUFFER_SIZE_INCREMENT 32 + +enum rmi_spi_op { + RMI_SPI_WRITE = 0, + RMI_SPI_READ, + RMI_SPI_V2_READ_UNIFIED, + RMI_SPI_V2_READ_SPLIT, + RMI_SPI_V2_WRITE, +}; + +struct rmi_spi_cmd { + enum rmi_spi_op op; + u16 addr; +}; + +struct rmi_spi_xport { + struct rmi_transport_dev xport; + struct spi_device *spi; + + struct mutex page_mutex; + int page; + + u8 *rx_buf; + u8 *tx_buf; + int xfer_buf_size; + + struct spi_transfer *rx_xfers; + struct spi_transfer *tx_xfers; + int rx_xfer_count; + int tx_xfer_count; +}; + +static int rmi_spi_manage_pools(struct rmi_spi_xport *rmi_spi, int len) +{ + struct spi_device *spi = rmi_spi->spi; + int buf_size = rmi_spi->xfer_buf_size + ? rmi_spi->xfer_buf_size : RMI_SPI_DEFAULT_XFER_BUF_SIZE; + struct spi_transfer *xfer_buf; + void *buf; + void *tmp; + + while (buf_size < len) + buf_size *= 2; + + if (buf_size > RMI_SPI_XFER_SIZE_LIMIT) + buf_size = RMI_SPI_XFER_SIZE_LIMIT; + + tmp = rmi_spi->rx_buf; + buf = devm_kzalloc(&spi->dev, buf_size * 2, + GFP_KERNEL | GFP_DMA); + if (!buf) + return -ENOMEM; + + rmi_spi->rx_buf = buf; + rmi_spi->tx_buf = &rmi_spi->rx_buf[buf_size]; + rmi_spi->xfer_buf_size = buf_size; + + if (tmp) + devm_kfree(&spi->dev, tmp); + + if (rmi_spi->xport.pdata.spi_data.read_delay_us) + rmi_spi->rx_xfer_count = buf_size; + else + rmi_spi->rx_xfer_count = 1; + + if (rmi_spi->xport.pdata.spi_data.write_delay_us) + rmi_spi->tx_xfer_count = buf_size; + else + rmi_spi->tx_xfer_count = 1; + + /* + * Allocate a pool of spi_transfer buffers for devices which need + * per byte delays. + */ + tmp = rmi_spi->rx_xfers; + xfer_buf = devm_kzalloc(&spi->dev, + (rmi_spi->rx_xfer_count + rmi_spi->tx_xfer_count) + * sizeof(struct spi_transfer), GFP_KERNEL); + if (!xfer_buf) + return -ENOMEM; + + rmi_spi->rx_xfers = xfer_buf; + rmi_spi->tx_xfers = &xfer_buf[rmi_spi->rx_xfer_count]; + + if (tmp) + devm_kfree(&spi->dev, tmp); + + return 0; +} + +static int rmi_spi_xfer(struct rmi_spi_xport *rmi_spi, + const struct rmi_spi_cmd *cmd, const u8 *tx_buf, + int tx_len, u8 *rx_buf, int rx_len) +{ + struct spi_device *spi = rmi_spi->spi; + struct rmi_device_platform_data_spi *spi_data = + &rmi_spi->xport.pdata.spi_data; + struct spi_message msg; + struct spi_transfer *xfer; + int ret = 0; + int len; + int cmd_len = 0; + int total_tx_len; + int i; + u16 addr = cmd->addr; + + spi_message_init(&msg); + + switch (cmd->op) { + case RMI_SPI_WRITE: + case RMI_SPI_READ: + cmd_len += 2; + break; + case RMI_SPI_V2_READ_UNIFIED: + case RMI_SPI_V2_READ_SPLIT: + case RMI_SPI_V2_WRITE: + cmd_len += 4; + break; + } + + total_tx_len = cmd_len + tx_len; + len = max(total_tx_len, rx_len); + + if (len > RMI_SPI_XFER_SIZE_LIMIT) + return -EINVAL; + + if (rmi_spi->xfer_buf_size < len) + rmi_spi_manage_pools(rmi_spi, len); + + if (addr == 0) + /* + * SPI needs an address. Use 0x7FF if we want to keep + * reading from the last position of the register pointer. + */ + addr = 0x7FF; + + switch (cmd->op) { + case RMI_SPI_WRITE: + rmi_spi->tx_buf[0] = (addr >> 8); + rmi_spi->tx_buf[1] = addr & 0xFF; + break; + case RMI_SPI_READ: + rmi_spi->tx_buf[0] = (addr >> 8) | 0x80; + rmi_spi->tx_buf[1] = addr & 0xFF; + break; + case RMI_SPI_V2_READ_UNIFIED: + break; + case RMI_SPI_V2_READ_SPLIT: + break; + case RMI_SPI_V2_WRITE: + rmi_spi->tx_buf[0] = 0x40; + rmi_spi->tx_buf[1] = (addr >> 8) & 0xFF; + rmi_spi->tx_buf[2] = addr & 0xFF; + rmi_spi->tx_buf[3] = tx_len; + break; + } + + if (tx_buf) + memcpy(&rmi_spi->tx_buf[cmd_len], tx_buf, tx_len); + + if (rmi_spi->tx_xfer_count > 1) { + for (i = 0; i < total_tx_len; i++) { + xfer = &rmi_spi->tx_xfers[i]; + memset(xfer, 0, sizeof(struct spi_transfer)); + xfer->tx_buf = &rmi_spi->tx_buf[i]; + xfer->len = 1; + xfer->delay_usecs = spi_data->write_delay_us; + spi_message_add_tail(xfer, &msg); + } + } else { + xfer = rmi_spi->tx_xfers; + memset(xfer, 0, sizeof(struct spi_transfer)); + xfer->tx_buf = rmi_spi->tx_buf; + xfer->len = total_tx_len; + spi_message_add_tail(xfer, &msg); + } + + dev_dbg(&spi->dev, "%s: cmd: %s tx_buf len: %d tx_buf: %*ph\n", + __func__, cmd->op == RMI_SPI_WRITE ? "WRITE" : "READ", + total_tx_len, total_tx_len, rmi_spi->tx_buf); + + if (rx_buf) { + if (rmi_spi->rx_xfer_count > 1) { + for (i = 0; i < rx_len; i++) { + xfer = &rmi_spi->rx_xfers[i]; + memset(xfer, 0, sizeof(struct spi_transfer)); + xfer->rx_buf = &rmi_spi->rx_buf[i]; + xfer->len = 1; + xfer->delay_usecs = spi_data->read_delay_us; + spi_message_add_tail(xfer, &msg); + } + } else { + xfer = rmi_spi->rx_xfers; + memset(xfer, 0, sizeof(struct spi_transfer)); + xfer->rx_buf = rmi_spi->rx_buf; + xfer->len = rx_len; + spi_message_add_tail(xfer, &msg); + } + } + + ret = spi_sync(spi, &msg); + if (ret < 0) { + dev_err(&spi->dev, "spi xfer failed: %d\n", ret); + return ret; + } + + if (rx_buf) { + memcpy(rx_buf, rmi_spi->rx_buf, rx_len); + dev_dbg(&spi->dev, "%s: (%d) %*ph\n", __func__, rx_len, + rx_len, rx_buf); + } + + return 0; +} + +/* + * rmi_set_page - Set RMI page + * @xport: The pointer to the rmi_transport_dev struct + * @page: The new page address. + * + * RMI devices have 16-bit addressing, but some of the transport + * implementations (like SMBus) only have 8-bit addressing. So RMI implements + * a page address at 0xff of every page so we can reliable page addresses + * every 256 registers. + * + * The page_mutex lock must be held when this function is entered. + * + * Returns zero on success, non-zero on failure. + */ +static int rmi_set_page(struct rmi_spi_xport *rmi_spi, u8 page) +{ + struct rmi_spi_cmd cmd; + int ret; + + cmd.op = RMI_SPI_WRITE; + cmd.addr = RMI_PAGE_SELECT_REGISTER; + + ret = rmi_spi_xfer(rmi_spi, &cmd, &page, 1, NULL, 0); + + if (ret) + rmi_spi->page = page; + + return ret; +} + +static int rmi_spi_write_block(struct rmi_transport_dev *xport, u16 addr, + const void *buf, size_t len) +{ + struct rmi_spi_xport *rmi_spi = + container_of(xport, struct rmi_spi_xport, xport); + struct rmi_spi_cmd cmd; + int ret; + + mutex_lock(&rmi_spi->page_mutex); + + if (RMI_SPI_PAGE(addr) != rmi_spi->page) { + ret = rmi_set_page(rmi_spi, RMI_SPI_PAGE(addr)); + if (ret) + goto exit; + } + + cmd.op = RMI_SPI_WRITE; + cmd.addr = addr; + + ret = rmi_spi_xfer(rmi_spi, &cmd, buf, len, NULL, 0); + +exit: + mutex_unlock(&rmi_spi->page_mutex); + return ret; +} + +static int rmi_spi_read_block(struct rmi_transport_dev *xport, u16 addr, + void *buf, size_t len) +{ + struct rmi_spi_xport *rmi_spi = + container_of(xport, struct rmi_spi_xport, xport); + struct rmi_spi_cmd cmd; + int ret; + + mutex_lock(&rmi_spi->page_mutex); + + if (RMI_SPI_PAGE(addr) != rmi_spi->page) { + ret = rmi_set_page(rmi_spi, RMI_SPI_PAGE(addr)); + if (ret) + goto exit; + } + + cmd.op = RMI_SPI_READ; + cmd.addr = addr; + + ret = rmi_spi_xfer(rmi_spi, &cmd, NULL, 0, buf, len); + +exit: + mutex_unlock(&rmi_spi->page_mutex); + return ret; +} + +static const struct rmi_transport_ops rmi_spi_ops = { + .write_block = rmi_spi_write_block, + .read_block = rmi_spi_read_block, +}; + +#ifdef CONFIG_OF +static int rmi_spi_of_probe(struct spi_device *spi, + struct rmi_device_platform_data *pdata) +{ + struct device *dev = &spi->dev; + int retval; + + retval = rmi_of_property_read_u32(dev, + &pdata->spi_data.read_delay_us, + "syna,spi-read-delay", 1); + if (retval) + return retval; + + retval = rmi_of_property_read_u32(dev, + &pdata->spi_data.write_delay_us, + "syna,spi-write-delay", 1); + if (retval) + return retval; + + return 0; +} + +static const struct of_device_id rmi_spi_of_match[] = { + { .compatible = "syna,rmi-spi" }, + {}, +}; +MODULE_DEVICE_TABLE(of, rmi_spi_of_match); +#else +static inline int rmi_spi_of_probe(struct spi_device *spi, + struct rmi_device_platform_data *pdata) +{ + return -ENODEV; +} +#endif + +static int rmi_spi_probe(struct spi_device *spi) +{ + struct rmi_spi_xport *rmi_spi; + struct rmi_device_platform_data *pdata; + struct rmi_device_platform_data *spi_pdata = spi->dev.platform_data; + int retval; + + if (spi->master->flags & SPI_MASTER_HALF_DUPLEX) + return -EINVAL; + + rmi_spi = devm_kzalloc(&spi->dev, sizeof(struct rmi_spi_xport), + GFP_KERNEL); + if (!rmi_spi) + return -ENOMEM; + + pdata = &rmi_spi->xport.pdata; + + if (spi->dev.of_node) { + retval = rmi_spi_of_probe(spi, pdata); + if (retval) + return retval; + } else if (spi_pdata) { + *pdata = *spi_pdata; + } + + if (pdata->spi_data.bits_per_word) + spi->bits_per_word = pdata->spi_data.bits_per_word; + + if (pdata->spi_data.mode) + spi->mode = pdata->spi_data.mode; + + retval = spi_setup(spi); + if (retval < 0) { + dev_err(&spi->dev, "spi_setup failed!\n"); + return retval; + } + + rmi_spi->spi = spi; + mutex_init(&rmi_spi->page_mutex); + + rmi_spi->xport.dev = &spi->dev; + rmi_spi->xport.proto_name = "spi"; + rmi_spi->xport.ops = &rmi_spi_ops; + rmi_spi->xport.irq = spi->irq; + + retval = rmi_spi_manage_pools(rmi_spi, RMI_SPI_DEFAULT_XFER_BUF_SIZE); + if (retval) + return retval; + + /* + * Setting the page to zero will (a) make sure the PSR is in a + * known state, and (b) make sure we can talk to the device. + */ + retval = rmi_set_page(rmi_spi, 0); + if (retval) { + dev_err(&spi->dev, "Failed to set page select to 0.\n"); + return retval; + } + + retval = rmi_register_transport_device(&rmi_spi->xport); + if (retval) { + dev_err(&spi->dev, "failed to register transport.\n"); + return retval; + } + + spi_set_drvdata(spi, rmi_spi); + + dev_info(&spi->dev, "registered RMI SPI driver\n"); + return 0; +} + +static int rmi_spi_remove(struct spi_device *spi) +{ + struct rmi_spi_xport *rmi_spi = spi_get_drvdata(spi); + + rmi_unregister_transport_device(&rmi_spi->xport); + + return 0; +} + +static const struct spi_device_id rmi_id[] = { + { "rmi_spi", 0 }, + { } +}; +MODULE_DEVICE_TABLE(spi, rmi_id); + +static struct spi_driver rmi_spi_driver = { + .driver = { + .owner = THIS_MODULE, + .name = "rmi_spi", + .of_match_table = of_match_ptr(rmi_spi_of_match), + }, + .id_table = rmi_id, + .probe = rmi_spi_probe, + .remove = rmi_spi_remove, +}; + +module_spi_driver(rmi_spi_driver); + +MODULE_AUTHOR("Christopher Heiny "); +MODULE_AUTHOR("Andrew Duggan "); +MODULE_DESCRIPTION("RMI SPI driver"); +MODULE_LICENSE("GPL"); +MODULE_VERSION(RMI_DRIVER_VERSION); diff --git a/include/linux/rmi.h b/include/linux/rmi.h index fef482a..c781d09 100644 --- a/include/linux/rmi.h +++ b/include/linux/rmi.h @@ -205,6 +205,8 @@ struct rmi_device_platform_data_spi { u32 split_read_byte_delay_us; u32 pre_delay_us; u32 post_delay_us; + u8 bits_per_word; + u16 mode; void *cs_assert_data; int (*cs_assert) (const void *cs_assert_data, const bool assert); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/