From patchwork Wed Jul 31 19:25:51 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gerhard Engleder X-Patchwork-Id: 816556 Received: from mx12lb.world4you.com (mx12lb.world4you.com [81.19.149.122]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 496F56EB5C for ; Wed, 31 Jul 2024 21:01:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=81.19.149.122 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722459708; cv=none; b=VREcyo8QjQFU5O980y1g2htqGvYg9jruGRAfHIkPJfbZnWcThDWSrNj4hu8ifrAV8RHLBpJ7QxxTb37ZZD0GQ6WqCWwhqW6RfdIYzMtfadul3aSEHML46ZoCWYsYIrcPbWfy+9C2NtG8wsvAHjR+sk0jEVX++FzCwY5JtN2UDgg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722459708; c=relaxed/simple; bh=kemKrNf+I+zwAwZbacBMTLWJi4d9r0Q5zLppG0S+9ps=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=VzKrbe4ukKgBPHHSXe+Ucd/1gkCe9Wadnj5mcPeUWlzR9q7E6SoPXwDsrCu53xEL8Q2sJMzCcle+FT8NhaLSYbSZq0bpffo9guB05axWZLyreem1WHNLwOQQwHmD8t4zlXcLsPga6pMNFgASRNjaVhoo9SghEG8QiUt+ch5kh28= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=engleder-embedded.com; spf=pass smtp.mailfrom=engleder-embedded.com; dkim=pass (1024-bit key) header.d=engleder-embedded.com header.i=@engleder-embedded.com header.b=VT7oaEPI; arc=none smtp.client-ip=81.19.149.122 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=engleder-embedded.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=engleder-embedded.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=engleder-embedded.com header.i=@engleder-embedded.com header.b="VT7oaEPI" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=engleder-embedded.com; s=dkim11; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=ODkupVVsjR45fX0YgcwHfi3kwe8QiGqg+SyzqMDzHsY=; b=VT7oaEPI43OMkCn2+2TsTWXY8s PWWR6HGdQF47KFFQ3SnQH5hT19ufuU37BEOSwoicH9Hn75c/Cl+mL7l6zP7SBdLJCzqkAYWPLs/8X H11cB5xW225B4MVrLAxiWxzroBBaiLlJh2kxUbaucQ3dNmN0PfafmuU6AthRfBGt5/vc=; Received: from 88-117-63-232.adsl.highway.telekom.at ([88.117.63.232] helo=hornet.engleder.at) by mx12lb.world4you.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96.2) (envelope-from ) id 1sZExU-0004If-2k; Wed, 31 Jul 2024 21:26:01 +0200 From: Gerhard Engleder To: linux-i2c@vger.kernel.org Cc: andi.shyti@kernel.org, Gerhard Engleder , Gerhard Engleder Subject: [PATCH v4 1/1] i2c: keba: Add KEBA I2C controller support Date: Wed, 31 Jul 2024 21:25:51 +0200 Message-Id: <20240731192551.94035-2-gerhard@engleder-embedded.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240731192551.94035-1-gerhard@engleder-embedded.com> References: <20240731192551.94035-1-gerhard@engleder-embedded.com> Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-AV-Do-Run: Yes X-ACL-Warn: X-W4Y-Internal From: Gerhard Engleder The KEBA I2C controller is found in the system FPGA of KEBA PLC devices. It is used to connect EEPROMs and hardware monitoring chips. The It is a simple I2C controller with a fixed bus speed of 100 kbit/s. The whole message transmission is executed by the driver. The driver triggers all steps over control, status and data register. There are no FIFOs or interrupts. Signed-off-by: Gerhard Engleder --- drivers/i2c/busses/Kconfig | 11 + drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-keba.c | 593 ++++++++++++++++++++++++++++++++++ 3 files changed, 605 insertions(+) create mode 100644 drivers/i2c/busses/i2c-keba.c diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index a22f9125322a..3d2215acc9b4 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -772,6 +772,17 @@ config I2C_JZ4780 If you don't know what to do here, say N. +config I2C_KEBA + tristate "KEBA I2C controller support" + depends on HAS_IOMEM + select AUXILIARY_BUS + help + This driver supports the I2C controller found in KEBA system FPGA + devices. + + This driver can also be built as a module. If so, the module + will be called i2c-keba. + config I2C_KEMPLD tristate "Kontron COM I2C Controller" depends on MFD_KEMPLD diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 78d0561339e5..ecc07c50f2a0 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -76,6 +76,7 @@ obj-$(CONFIG_I2C_IMX) += i2c-imx.o obj-$(CONFIG_I2C_IMX_LPI2C) += i2c-imx-lpi2c.o obj-$(CONFIG_I2C_IOP3XX) += i2c-iop3xx.o obj-$(CONFIG_I2C_JZ4780) += i2c-jz4780.o +obj-$(CONFIG_I2C_KEBA) += i2c-keba.o obj-$(CONFIG_I2C_KEMPLD) += i2c-kempld.o obj-$(CONFIG_I2C_LPC2K) += i2c-lpc2k.o obj-$(CONFIG_I2C_LS2X) += i2c-ls2x.o diff --git a/drivers/i2c/busses/i2c-keba.c b/drivers/i2c/busses/i2c-keba.c new file mode 100644 index 000000000000..400015e4ac77 --- /dev/null +++ b/drivers/i2c/busses/i2c-keba.c @@ -0,0 +1,593 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) KEBA Industrial Automation Gmbh 2024 + * + * Driver for KEBA I2C controller FPGA IP core + */ + +#include +#include +#include +#include +#include + +#define KI2C "i2c-keba" + +#define KI2C_CAPABILITY_REG 0x02 +#define KI2C_CAPABILITY_CRYPTO 0x01 +#define KI2C_CAPABILITY_DC 0x02 + +#define KI2C_CONTROL_REG 0x04 +#define KI2C_CONTROL_MEN 0x01 +#define KI2C_CONTROL_MSTA 0x02 +#define KI2C_CONTROL_RSTA 0x04 +#define KI2C_CONTROL_MTX 0x08 +#define KI2C_CONTROL_TXAK 0x10 +#define KI2C_CONTROL_DISABLE 0x00 + +#define KI2C_CONTROL_DC_REG 0x05 +#define KI2C_CONTROL_DC_SDA 0x01 +#define KI2C_CONTROL_DC_SCL 0x02 + +#define KI2C_STATUS_REG 0x08 +#define KI2C_STATUS_IN_USE 0x01 +#define KI2C_STATUS_ACK_CYC 0x02 +#define KI2C_STATUS_RXAK 0x04 +#define KI2C_STATUS_MCF 0x08 + +#define KI2C_STATUS_DC_REG 0x09 +#define KI2C_STATUS_DC_SDA 0x01 +#define KI2C_STATUS_DC_SCL 0x02 + +#define KI2C_DATA_REG 0x0c + +#define KI2C_INUSE_SLEEP_US (2 * USEC_PER_MSEC) +#define KI2C_INUSE_TIMEOUT_US (10 * USEC_PER_SEC) + +#define KI2C_POLL_DELAY_US 5 + +struct ki2c { + struct keba_i2c_auxdev *auxdev; + void __iomem *base; + struct i2c_adapter adapter; + + struct i2c_client **client; + int client_size; +}; + +static int ki2c_inuse_lock(struct ki2c *ki2c) +{ + u8 sts; + int ret; + + /* + * The I2C controller has an IN_USE bit for locking access to the + * controller. This enables the use of I2C controller by other none + * Linux processors. + * + * If the I2C controller is free, then the first read returns + * IN_USE == 0. After that the I2C controller is locked and further + * reads of IN_USE return 1. + * + * The I2C controller is unlocked by writing 1 into IN_USE. + * + * The IN_USE bit acts as a hardware semaphore for the I2C controller. + * Poll for semaphore, but sleep while polling to free the CPU. + */ + ret = readb_poll_timeout(ki2c->base + KI2C_STATUS_REG, + sts, (sts & KI2C_STATUS_IN_USE) == 0, + KI2C_INUSE_SLEEP_US, KI2C_INUSE_TIMEOUT_US); + if (ret != 0) + dev_warn(&ki2c->auxdev->auxdev.dev, "%s err!\n", __func__); + + return ret; +} + +static void ki2c_inuse_unlock(struct ki2c *ki2c) +{ + /* unlock the controller by writing 1 into IN_USE */ + iowrite8(KI2C_STATUS_IN_USE, ki2c->base + KI2C_STATUS_REG); +} + +static int ki2c_wait_for_bit(void __iomem *addr, u8 mask, unsigned long timeout) +{ + u8 val; + + return readb_poll_timeout(addr, val, (val & mask), KI2C_POLL_DELAY_US, + jiffies_to_usecs(timeout)); +} + +static int ki2c_wait_for_mcf(struct ki2c *ki2c) +{ + return ki2c_wait_for_bit(ki2c->base + KI2C_STATUS_REG, KI2C_STATUS_MCF, + ki2c->adapter.timeout); +} + +static int ki2c_wait_for_data(struct ki2c *ki2c) +{ + int ret; + + ret = ki2c_wait_for_mcf(ki2c); + if (ret < 0) + return ret; + + return ki2c_wait_for_bit(ki2c->base + KI2C_STATUS_REG, + KI2C_STATUS_ACK_CYC, + ki2c->adapter.timeout); +} + +static int ki2c_wait_for_data_ack(struct ki2c *ki2c) +{ + unsigned int reg; + int ret; + + ret = ki2c_wait_for_data(ki2c); + if (ret < 0) + return ret; + + /* RXAK == 0 means ACK reveived */ + reg = ioread8(ki2c->base + KI2C_STATUS_REG); + if (reg & KI2C_STATUS_RXAK) + return -EIO; + + return 0; +} + +static int ki2c_has_capability(struct ki2c *ki2c, unsigned int cap) +{ + unsigned int reg = ioread8(ki2c->base + KI2C_CAPABILITY_REG); + + return (reg & cap) != 0; +} + +static int ki2c_get_scl(struct ki2c *ki2c) +{ + unsigned int reg = ioread8(ki2c->base + KI2C_STATUS_DC_REG); + + /* capability KI2C_CAPABILITY_DC required */ + return (reg & KI2C_STATUS_DC_SCL) != 0; +} + +static int ki2c_get_sda(struct ki2c *ki2c) +{ + unsigned int reg = ioread8(ki2c->base + KI2C_STATUS_DC_REG); + + /* capability KI2C_CAPABILITY_DC required */ + return (reg & KI2C_STATUS_DC_SDA) != 0; +} + +static void ki2c_set_scl(struct ki2c *ki2c, int val) +{ + u8 control_dc; + + /* capability KI2C_CAPABILITY_DC and KI2C_CONTROL_MEN = 0 reqired */ + control_dc = ioread8(ki2c->base + KI2C_CONTROL_DC_REG); + if (val) + control_dc |= KI2C_CONTROL_DC_SCL; + else + control_dc &= ~KI2C_CONTROL_DC_SCL; + iowrite8(control_dc, ki2c->base + KI2C_CONTROL_DC_REG); +} + +/* + * Resetting bus bitwise is done by checking SDA and applying clock cycles as + * long as SDA is low. 9 clock cycles are applied at most. + * + * Clock cycles are generated and ndelay() determines the duration of clock + * cycles. Generated clock rate is 100 KHz and so duration of both clock levels + * is: delay in ns = (10^6 / 100) / 2 + */ +#define KI2C_RECOVERY_CLK_CNT 9 +#define KI2C_RECOVERY_NDELAY 5000 +static int ki2c_reset_bus_bitwise(struct ki2c *ki2c) +{ + int count = 0; + int val = 1; + int ret = 0; + + /* disable I2C controller (MEN = 0) to get direct access to SCL/SDA */ + iowrite8(0, ki2c->base + KI2C_CONTROL_REG); + + /* generate clock cycles */ + ki2c_set_scl(ki2c, val); + ndelay(KI2C_RECOVERY_NDELAY); + while (count++ < KI2C_RECOVERY_CLK_CNT * 2) { + if (val) { + /* SCL shouldn't be low here */ + if (!ki2c_get_scl(ki2c)) { + dev_err(&ki2c->auxdev->auxdev.dev, + "SCL is stuck low!\n"); + ret = -EBUSY; + break; + } + + /* break if SDA is high */ + if (ki2c_get_sda(ki2c)) + break; + } + + val = !val; + ki2c_set_scl(ki2c, val); + ndelay(KI2C_RECOVERY_NDELAY); + } + + if (!ki2c_get_sda(ki2c)) { + dev_err(&ki2c->auxdev->auxdev.dev, "SDA is still low!\n"); + ret = -EBUSY; + } + + /* reenable controller */ + iowrite8(KI2C_CONTROL_MEN, ki2c->base + KI2C_CONTROL_REG); + + return ret; +} + +/* + * Resetting bus bytewise is done by writing start bit, 9 data bits and stop + * bit. + * + * This is not 100% safe. If slave is an EEPROM and a write access was + * interrupted during the ACK cycle, this approach might not be able to recover + * the bus. The reason is, that after the 9 clock cycles the EEPROM will be in + * ACK cycle again and will hold SDA low like it did before the start of the + * routine. Furthermore the EEPROM might get written one additional byte with + * 0xff into it. Thus, use bitwise approach whenever possible, especially when + * EEPROMs are on the bus. + */ +static int ki2c_reset_bus_bytewise(struct ki2c *ki2c) +{ + int ret; + + /* hold data line high for 9 clock cycles */ + iowrite8(0xFF, ki2c->base + KI2C_DATA_REG); + + /* create start condition */ + iowrite8(KI2C_CONTROL_MEN | KI2C_CONTROL_MTX | KI2C_CONTROL_MSTA | KI2C_CONTROL_TXAK, + ki2c->base + KI2C_CONTROL_REG); + ret = ki2c_wait_for_mcf(ki2c); + if (ret < 0) { + dev_err(&ki2c->auxdev->auxdev.dev, "Start condition failed\n"); + + return ret; + } + + /* create stop condition */ + iowrite8(KI2C_CONTROL_MEN | KI2C_CONTROL_MTX | KI2C_CONTROL_TXAK, + ki2c->base + KI2C_CONTROL_REG); + ret = ki2c_wait_for_mcf(ki2c); + if (ret < 0) + dev_err(&ki2c->auxdev->auxdev.dev, "Stop condition failed\n"); + + return ret; +} + +static int ki2c_reset_bus(struct ki2c *ki2c) +{ + int ret; + + ret = ki2c_inuse_lock(ki2c); + if (ret < 0) + return ret; + + /* + * If the I2C controller is capable of direct control of SCL/SDA, then a + * bitwise reset is used. Otherwise fall back to bytewise reset. + */ + if (ki2c_has_capability(ki2c, KI2C_CAPABILITY_DC)) + ret = ki2c_reset_bus_bitwise(ki2c); + else + ret = ki2c_reset_bus_bytewise(ki2c); + + ki2c_inuse_unlock(ki2c); + + return ret; +} + +static void ki2c_write_target_addr(struct ki2c *ki2c, struct i2c_msg *m) +{ + u8 addr; + + addr = m->addr << 1; + /* Bit 0 signals RD/WR */ + if (m->flags & I2C_M_RD) + addr |= 0x01; + + iowrite8(addr, ki2c->base + KI2C_DATA_REG); +} + +static int ki2c_start_addr(struct ki2c *ki2c, struct i2c_msg *m) +{ + int ret; + + /* + * Store target address byte in the controller. This has to be done + * before sending START condition. + */ + ki2c_write_target_addr(ki2c, m); + + /* enable controller for TX */ + iowrite8(KI2C_CONTROL_MEN | KI2C_CONTROL_MTX, + ki2c->base + KI2C_CONTROL_REG); + + /* send START condition and target address byte */ + iowrite8(KI2C_CONTROL_MEN | KI2C_CONTROL_MTX | KI2C_CONTROL_MSTA, + ki2c->base + KI2C_CONTROL_REG); + + ret = ki2c_wait_for_data_ack(ki2c); + if (ret < 0) + /* + * For EEPROMs this is normal behavior during internal write + * operation. + */ + dev_dbg(&ki2c->auxdev->auxdev.dev, + "%s wait for ACK err at 0x%02x!\n", __func__, m->addr); + + return ret; +} + +static int ki2c_repstart_addr(struct ki2c *ki2c, struct i2c_msg *m) +{ + int ret; + + /* repeated start and write is not supported */ + if ((m->flags & I2C_M_RD) == 0) { + dev_warn(&ki2c->auxdev->auxdev.dev, + "Repeated start not supported for writes\n"); + return -EINVAL; + } + + /* send repeated start */ + iowrite8(KI2C_CONTROL_MEN | KI2C_CONTROL_MSTA | KI2C_CONTROL_RSTA, + ki2c->base + KI2C_CONTROL_REG); + + ret = ki2c_wait_for_mcf(ki2c); + if (ret < 0) { + dev_warn(&ki2c->auxdev->auxdev.dev, + "%s wait for MCF err at 0x%02x!\n", __func__, m->addr); + return ret; + } + + /* write target-address byte */ + ki2c_write_target_addr(ki2c, m); + + ret = ki2c_wait_for_data_ack(ki2c); + if (ret < 0) + dev_warn(&ki2c->auxdev->auxdev.dev, + "%s wait for ACK err at 0x%02x!\n", __func__, m->addr); + + return ret; +} + +static void ki2c_stop(struct ki2c *ki2c) +{ + iowrite8(KI2C_CONTROL_MEN, ki2c->base + KI2C_CONTROL_REG); + ki2c_wait_for_mcf(ki2c); +} + +static int ki2c_write(struct ki2c *ki2c, const u8 *data, int len) +{ + int ret; + + for (int i = 0; i < len; i++) { + /* write data byte */ + iowrite8(data[i], ki2c->base + KI2C_DATA_REG); + + ret = ki2c_wait_for_data_ack(ki2c); + if (ret < 0) + return ret; + } + + return 0; +} + +static int ki2c_read(struct ki2c *ki2c, u8 *data, int len) +{ + u8 control; + int ret; + + if (len == 0) + return 0; /* nothing to do */ + + control = KI2C_CONTROL_MEN | KI2C_CONTROL_MSTA; + + /* if just one byte => send tx-nack after transfer */ + if (len == 1) + control |= KI2C_CONTROL_TXAK; + + iowrite8(control, ki2c->base + KI2C_CONTROL_REG); + + /* dummy read to start transfer on bus */ + ioread8(ki2c->base + KI2C_DATA_REG); + + for (int i = 0; i < len; i++) { + ret = ki2c_wait_for_data(ki2c); + if (ret < 0) + return ret; + + /* send tx-nack after transfer of last byte */ + if (i == len - 2) + iowrite8(KI2C_CONTROL_MEN | KI2C_CONTROL_MSTA | KI2C_CONTROL_TXAK, + ki2c->base + KI2C_CONTROL_REG); + + /* + * switch to TX on last byte, so that reading DATA-register + * does not trigger another read transfer. + */ + if (i == len - 1) + iowrite8(KI2C_CONTROL_MEN | KI2C_CONTROL_MSTA | KI2C_CONTROL_MTX, + ki2c->base + KI2C_CONTROL_REG); + + /* read byte and start next transfer (if not last byte) */ + data[i] = ioread8(ki2c->base + KI2C_DATA_REG); + } + + return len; +} + +static int ki2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + struct ki2c *ki2c = i2c_get_adapdata(adap); + int ret; + + ret = ki2c_inuse_lock(ki2c); + if (ret < 0) + return ret; + + for (int i = 0; i < num; i++) { + struct i2c_msg *m = &msgs[i]; + + if (i == 0) + ret = ki2c_start_addr(ki2c, m); + else + ret = ki2c_repstart_addr(ki2c, m); + if (ret < 0) + break; + + if (m->flags & I2C_M_RD) + ret = ki2c_read(ki2c, m->buf, m->len); + else + ret = ki2c_write(ki2c, m->buf, m->len); + if (ret < 0) + break; + } + + ki2c_stop(ki2c); + + ki2c_inuse_unlock(ki2c); + + return (ret < 0) ? ret : num; +} + +static void ki2c_unregister_devices(struct ki2c *ki2c) +{ + for (int i = 0; i < ki2c->client_size; i++) { + struct i2c_client *client = ki2c->client[i]; + + if (client) + i2c_unregister_device(client); + } +} + +static int ki2c_register_devices(struct ki2c *ki2c) +{ + struct i2c_board_info *info = ki2c->auxdev->info; + int i; + + /* register all I2C devices from platform_data array */ + for (i = 0; i < ki2c->client_size; i++) { + struct i2c_client *client; + unsigned short const addr_list[2] = { info[i].addr, + I2C_CLIENT_END }; + + client = i2c_new_scanned_device(&ki2c->adapter, &info[i], + addr_list, NULL); + if (!IS_ERR(client)) { + ki2c->client[i] = client; + } else if (PTR_ERR(client) != -ENODEV) { + ki2c_unregister_devices(ki2c); + + return PTR_ERR(client); + } + } + + return 0; +} + +static u32 ki2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm ki2c_algo = { + .master_xfer = ki2c_xfer, + .functionality = ki2c_func, +}; + +static int ki2c_probe(struct auxiliary_device *auxdev, + const struct auxiliary_device_id *id) +{ + struct device *dev = &auxdev->dev; + struct i2c_adapter *adap; + struct ki2c *ki2c; + int ret; + + ki2c = devm_kzalloc(dev, sizeof(*ki2c), GFP_KERNEL); + if (!ki2c) + return -ENOMEM; + ki2c->auxdev = container_of(auxdev, struct keba_i2c_auxdev, auxdev); + ki2c->client = devm_kcalloc(dev, ki2c->auxdev->info_size, + sizeof(*ki2c->client), GFP_KERNEL); + if (!ki2c->client) + return -ENOMEM; + ki2c->client_size = ki2c->auxdev->info_size; + auxiliary_set_drvdata(auxdev, ki2c); + + ki2c->base = devm_ioremap_resource(dev, &ki2c->auxdev->io); + if (IS_ERR(ki2c->base)) + return PTR_ERR(ki2c->base); + + adap = &ki2c->adapter; + strscpy(adap->name, "KEBA I2C adapter", sizeof(adap->name)); + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_HWMON; + adap->algo = &ki2c_algo; + adap->dev.parent = dev; + + i2c_set_adapdata(adap, ki2c); + + /* enable controller */ + iowrite8(KI2C_CONTROL_MEN, ki2c->base + KI2C_CONTROL_REG); + + /* reset bus before probing I2C devices */ + ret = ki2c_reset_bus(ki2c); + if (ret) + goto out; + + ret = devm_i2c_add_adapter(dev, adap); + if (ret) { + dev_err(dev, "Failed to add adapter (%d)!\n", ret); + goto out; + } + + ret = ki2c_register_devices(ki2c); + if (ret) { + dev_err(dev, "Failed to register devices (%d)!\n", ret); + goto out; + } + + return 0; + +out: + iowrite8(KI2C_CONTROL_DISABLE, ki2c->base + KI2C_CONTROL_REG); + return ret; +} + +static void ki2c_remove(struct auxiliary_device *auxdev) +{ + struct ki2c *ki2c = auxiliary_get_drvdata(auxdev); + + ki2c_unregister_devices(ki2c); + + /* disable controller */ + iowrite8(KI2C_CONTROL_DISABLE, ki2c->base + KI2C_CONTROL_REG); + + auxiliary_set_drvdata(auxdev, NULL); +} + +static const struct auxiliary_device_id ki2c_devtype_aux[] = { + { .name = "keba.i2c" }, + { }, +}; +MODULE_DEVICE_TABLE(auxiliary, ki2c_devtype_aux); + +static struct auxiliary_driver ki2c_driver_aux = { + .name = KI2C, + .id_table = ki2c_devtype_aux, + .probe = ki2c_probe, + .remove = ki2c_remove, +}; +module_auxiliary_driver(ki2c_driver_aux); + +MODULE_AUTHOR("Gerhard Engleder "); +MODULE_DESCRIPTION("KEBA I2C bus controller driver"); +MODULE_LICENSE("GPL");