From patchwork Fri Jul 8 10:03:50 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Phil Edworthy X-Patchwork-Id: 12910862 X-Patchwork-Delegate: geert@linux-m68k.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C81DCCCA480 for ; Fri, 8 Jul 2022 10:04:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237763AbiGHKEe (ORCPT ); Fri, 8 Jul 2022 06:04:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50636 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237707AbiGHKEd (ORCPT ); Fri, 8 Jul 2022 06:04:33 -0400 Received: from relmlie5.idc.renesas.com (relmlor1.renesas.com [210.160.252.171]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id A53E321E01; Fri, 8 Jul 2022 03:04:31 -0700 (PDT) X-IronPort-AV: E=Sophos;i="5.92,255,1650898800"; d="scan'208";a="125552209" Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie5.idc.renesas.com with ESMTP; 08 Jul 2022 19:04:31 +0900 Received: from localhost.localdomain (unknown [10.226.92.28]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id C17644006192; Fri, 8 Jul 2022 19:04:25 +0900 (JST) From: Phil Edworthy To: Philipp Zabel Cc: Phil Edworthy , Wolfram Sang , Andy Shevchenko , Jarkko Nikula , Krzysztof Kozlowski , Sam Protsenko , Rob Herring , Sven Peter , Jan Dabros , Lukas Bulwahn , Tyrone Ting , Arnd Bergmann , Olof Johansson , Biju Das , Geert Uytterhoeven , linux-i2c@vger.kernel.org, linux-renesas-soc@vger.kernel.org Subject: [PATCH v4 2/2] i2c: Add Renesas RZ/V2M controller Date: Fri, 8 Jul 2022 11:03:50 +0100 Message-Id: <20220708100350.12523-3-phil.edworthy@renesas.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220708100350.12523-1-phil.edworthy@renesas.com> References: <20220708100350.12523-1-phil.edworthy@renesas.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org Yet another i2c controller from Renesas that is found on the RZ/V2M (r9a09g011) SoC. It can support only 100kHz and 400KHz operation. Signed-off-by: Phil Edworthy Reviewed-by: Biju Das Reviewed-by: Andy Shevchenko Reviewed-by: Philipp Zabel --- v4: - Multiline comment fix - Use GENMASK - Fix too many parentheses - Better use of sizeof() - Move MODULE_DEVICE_TABLE close to use - Use pm_runtime_resume_and_get() and check return val - Replace NOIRQ_SYSTEM_SLEEP_PM_OPS with SYSTEM_SLEEP_PM_OPS so we can use runtime PM in suspend and resume. v3: - Lots of small fixes base don Andy Shevchenko's review - Use devm_reset_control_get_shared() instead of devm_reset_control_get() v2: - Use the new NOIRQ_SYSTEM_SLEEP_PM_OPS() as suggested by Arnd - Lots of small fixes based on Geert's review --- drivers/i2c/busses/Kconfig | 10 + drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-rzv2m.c | 533 +++++++++++++++++++++++++++++++++ 3 files changed, 544 insertions(+) create mode 100644 drivers/i2c/busses/i2c-rzv2m.c diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index b1d7069dd377..9e3f9eb1ea3c 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -984,6 +984,16 @@ config I2C_RK3X This driver can also be built as a module. If so, the module will be called i2c-rk3x. +config I2C_RZV2M + tristate "Renesas RZ/V2M adapter" + depends on ARCH_RENESAS || COMPILE_TEST + help + If you say yes to this option, support will be included for the + Renesas RZ/V2M I2C interface. + + This driver can also be built as a module. If so, the module + will be called i2c-rzv2m. + config I2C_S3C2410 tristate "S3C/Exynos I2C Driver" depends on ARCH_EXYNOS || ARCH_S3C24XX || ARCH_S3C64XX || \ diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index b0a10e5d9ee9..7792ffc591f0 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -101,6 +101,7 @@ obj-$(CONFIG_I2C_QCOM_GENI) += i2c-qcom-geni.o obj-$(CONFIG_I2C_QUP) += i2c-qup.o obj-$(CONFIG_I2C_RIIC) += i2c-riic.o obj-$(CONFIG_I2C_RK3X) += i2c-rk3x.o +obj-$(CONFIG_I2C_RZV2M) += i2c-rzv2m.o obj-$(CONFIG_I2C_S3C2410) += i2c-s3c2410.o obj-$(CONFIG_I2C_SH7760) += i2c-sh7760.o obj-$(CONFIG_I2C_SH_MOBILE) += i2c-sh_mobile.o diff --git a/drivers/i2c/busses/i2c-rzv2m.c b/drivers/i2c/busses/i2c-rzv2m.c new file mode 100644 index 000000000000..156bfef0dcd0 --- /dev/null +++ b/drivers/i2c/busses/i2c-rzv2m.c @@ -0,0 +1,533 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for the Renesas RZ/V2M I2C unit + * + * Copyright (C) 2016-2022 Renesas Electronics Corporation + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Register offsets */ +#define IICB0DAT 0x00 /* Data Register */ +#define IICB0CTL0 0x08 /* Control Register 0 */ +#define IICB0TRG 0x0C /* Trigger Register */ +#define IICB0STR0 0x10 /* Status Register 0 */ +#define IICB0CTL1 0x20 /* Control Register 1 */ +#define IICB0WL 0x24 /* Low Level Width Setting Reg */ +#define IICB0WH 0x28 /* How Level Width Setting Reg */ + +/* IICB0CTL0 */ +#define IICB0IICE BIT(7) /* I2C Enable */ +#define IICB0SLWT BIT(1) /* Interrupt Request Timing */ +#define IICB0SLAC BIT(0) /* Acknowledge */ + +/* IICB0TRG */ +#define IICB0WRET BIT(2) /* Quit Wait Trigger */ +#define IICB0STT BIT(1) /* Create Start Condition Trigger */ +#define IICB0SPT BIT(0) /* Create Stop Condition Trigger */ + +/* IICB0STR0 */ +#define IICB0SSAC BIT(8) /* Ack Flag */ +#define IICB0SSBS BIT(6) /* Bus Flag */ +#define IICB0SSSP BIT(4) /* Stop Condition Flag */ + +/* IICB0CTL1 */ +#define IICB0MDSC BIT(7) /* Bus Mode */ +#define IICB0SLSE BIT(1) /* Start condition output */ + +#define bit_setl(addr, val) writel(readl(addr) | (val), (addr)) +#define bit_clrl(addr, val) writel(readl(addr) & ~(val), (addr)) + +struct rzv2m_i2c_priv { + void __iomem *base; + struct i2c_adapter adap; + struct clk *clk; + int bus_mode; + struct completion msg_tia_done; + u32 iicb0wl; + u32 iicb0wh; +}; + +enum bcr_index { + RZV2M_I2C_100K = 0, + RZV2M_I2C_400K, +}; + +struct bitrate_config { + unsigned int percent_low; + unsigned int min_hold_time_ns; +}; + +static const struct bitrate_config bitrate_configs[] = { + [RZV2M_I2C_100K] = { 47, 3450 }, + [RZV2M_I2C_400K] = { 52, 900 }, +}; + +static irqreturn_t rzv2m_i2c_tia_irq_handler(int this_irq, void *dev_id) +{ + struct rzv2m_i2c_priv *priv = dev_id; + + complete(&priv->msg_tia_done); + + return IRQ_HANDLED; +} + +/* Calculate IICB0WL and IICB0WH */ +static int rzv2m_i2c_clock_calculate(struct device *dev, + struct rzv2m_i2c_priv *priv) +{ + const struct bitrate_config *config; + unsigned int hold_time_ns; + unsigned int total_pclks; + unsigned int trf_pclks; + unsigned long pclk_hz; + struct i2c_timings t; + u32 trf_ns; + + i2c_parse_fw_timings(dev, &t, true); + + pclk_hz = clk_get_rate(priv->clk); + total_pclks = pclk_hz / t.bus_freq_hz; + + trf_ns = t.scl_rise_ns + t.scl_fall_ns; + trf_pclks = mul_u64_u32_div(pclk_hz, trf_ns, NSEC_PER_SEC); + + /* Config setting */ + switch (t.bus_freq_hz) { + case I2C_MAX_FAST_MODE_FREQ: + priv->bus_mode = RZV2M_I2C_400K; + break; + case I2C_MAX_STANDARD_MODE_FREQ: + priv->bus_mode = RZV2M_I2C_100K; + break; + default: + dev_err(dev, "transfer speed is invalid\n"); + return -EINVAL; + } + config = &bitrate_configs[priv->bus_mode]; + + /* IICB0WL = (percent_low / Transfer clock) x PCLK */ + priv->iicb0wl = total_pclks * config->percent_low / 100; + if (priv->iicb0wl > (BIT(10) - 1)) + return -EINVAL; + + /* IICB0WH = ((percent_high / Transfer clock) x PCLK) - (tR + tF) */ + priv->iicb0wh = total_pclks - priv->iicb0wl - trf_pclks; + if (priv->iicb0wh > (BIT(10) - 1)) + return -EINVAL; + + /* + * Data hold time must be less than 0.9us in fast mode and + * 3.45us in standard mode. + * Data hold time = IICB0WL[9:2] / PCLK + */ + hold_time_ns = div64_ul((u64)(priv->iicb0wl >> 2) * NSEC_PER_SEC, pclk_hz); + if (hold_time_ns > config->min_hold_time_ns) { + dev_err(dev, "data hold time %dns is over %dns\n", + hold_time_ns, config->min_hold_time_ns); + return -EINVAL; + } + + return 0; +} + +static void rzv2m_i2c_init(struct rzv2m_i2c_priv *priv) +{ + u32 i2c_ctl0; + u32 i2c_ctl1; + + /* i2c disable */ + writel(0, priv->base + IICB0CTL0); + + /* IICB0CTL1 setting */ + i2c_ctl1 = IICB0SLSE; + if (priv->bus_mode == RZV2M_I2C_400K) + i2c_ctl1 |= IICB0MDSC; + writel(i2c_ctl1, priv->base + IICB0CTL1); + + /* IICB0WL IICB0WH setting */ + writel(priv->iicb0wl, priv->base + IICB0WL); + writel(priv->iicb0wh, priv->base + IICB0WH); + + /* i2c enable after setting */ + i2c_ctl0 = IICB0SLWT | IICB0SLAC | IICB0IICE; + writel(i2c_ctl0, priv->base + IICB0CTL0); +} + +static int rzv2m_i2c_write_with_ack(struct rzv2m_i2c_priv *priv, u32 data) +{ + unsigned long time_left; + + reinit_completion(&priv->msg_tia_done); + + writel(data, priv->base + IICB0DAT); + + time_left = wait_for_completion_timeout(&priv->msg_tia_done, + priv->adap.timeout); + if (!time_left) + return -ETIMEDOUT; + + /* Confirm ACK */ + if ((readl(priv->base + IICB0STR0) & IICB0SSAC) != IICB0SSAC) + return -ENXIO; + + return 0; +} + +static int rzv2m_i2c_read_with_ack(struct rzv2m_i2c_priv *priv, u8 *data, + bool last) +{ + unsigned long time_left; + u32 data_tmp; + + reinit_completion(&priv->msg_tia_done); + + /* Interrupt request timing : 8th clock */ + bit_clrl(priv->base + IICB0CTL0, IICB0SLWT); + + /* Exit the wait state */ + writel(IICB0WRET, priv->base + IICB0TRG); + + /* Wait for transaction */ + time_left = wait_for_completion_timeout(&priv->msg_tia_done, + priv->adap.timeout); + if (!time_left) + return -ETIMEDOUT; + + if (last) { + /* Disable ACK */ + bit_clrl(priv->base + IICB0CTL0, IICB0SLAC); + + /* Read data*/ + data_tmp = readl(priv->base + IICB0DAT); + + /* Interrupt request timing : 9th clock */ + bit_setl(priv->base + IICB0CTL0, IICB0SLWT); + + /* Exit the wait state */ + writel(IICB0WRET, priv->base + IICB0TRG); + + /* Wait for transaction */ + time_left = wait_for_completion_timeout(&priv->msg_tia_done, + priv->adap.timeout); + if (!time_left) + return -ETIMEDOUT; + + /* Enable ACK */ + bit_setl(priv->base + IICB0CTL0, IICB0SLAC); + } else { + /* Read data */ + data_tmp = readl(priv->base + IICB0DAT); + } + + *data = data_tmp; + + return 0; +} + +static int rzv2m_i2c_send(struct rzv2m_i2c_priv *priv, struct i2c_msg *msg, + unsigned int *count) +{ + unsigned int i; + int ret; + + for (i = 0; i < msg->len; i++) { + ret = rzv2m_i2c_write_with_ack(priv, msg->buf[i]); + if (ret < 0) + return ret; + } + *count = i; + + return 0; +} + +static int rzv2m_i2c_receive(struct rzv2m_i2c_priv *priv, struct i2c_msg *msg, + unsigned int *count) +{ + unsigned int i; + int ret; + + for (i = 0; i < msg->len; i++) { + ret = rzv2m_i2c_read_with_ack(priv, &msg->buf[i], + (msg->len - 1) == i); + if (ret < 0) + return ret; + } + *count = i; + + return 0; +} + +static int rzv2m_i2c_send_address(struct rzv2m_i2c_priv *priv, + struct i2c_msg *msg) +{ + u32 addr; + int ret; + + if (msg->flags & I2C_M_TEN) { + /* + * 10-bit address + * addr_1: 5'b11110 | addr[9:8] | (R/nW) + * addr_2: addr[7:0] + */ + addr = 0xf0 | ((msg->addr & GENMASK(9, 8)) >> 7); + addr |= !!(msg->flags & I2C_M_RD); + /* Send 1st address(extend code) */ + ret = rzv2m_i2c_write_with_ack(priv, addr); + if (ret) + return ret; + + /* Send 2nd address */ + ret = rzv2m_i2c_write_with_ack(priv, msg->addr & 0xff); + } else { + /* 7-bit address */ + addr = i2c_8bit_addr_from_msg(msg); + ret = rzv2m_i2c_write_with_ack(priv, addr); + } + + return ret; +} + +static int rzv2m_i2c_stop_condition(struct rzv2m_i2c_priv *priv) +{ + u32 value; + + /* Send stop condition */ + writel(IICB0SPT, priv->base + IICB0TRG); + return readl_poll_timeout(priv->base + IICB0STR0, + value, value & IICB0SSSP, + 100, jiffies_to_usecs(priv->adap.timeout)); +} + +static int rzv2m_i2c_master_xfer1(struct rzv2m_i2c_priv *priv, + struct i2c_msg *msg, int stop) +{ + unsigned int count = 0; + int ret, read = !!(msg->flags & I2C_M_RD); + + /* Send start condition */ + writel(IICB0STT, priv->base + IICB0TRG); + + ret = rzv2m_i2c_send_address(priv, msg); + if (!ret) { + if (read) + ret = rzv2m_i2c_receive(priv, msg, &count); + else + ret = rzv2m_i2c_send(priv, msg, &count); + + if (!ret && stop) + ret = rzv2m_i2c_stop_condition(priv); + } + + if (ret == -ENXIO) + rzv2m_i2c_stop_condition(priv); + else if (ret < 0) + rzv2m_i2c_init(priv); + else + ret = count; + + return ret; +} + +static int rzv2m_i2c_master_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct rzv2m_i2c_priv *priv = i2c_get_adapdata(adap); + struct device *dev = priv->adap.dev.parent; + unsigned int i; + int ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) + return ret; + + if (readl(priv->base + IICB0STR0) & IICB0SSBS) { + ret = -EAGAIN; + goto out; + } + + /* I2C main transfer */ + for (i = 0; i < num; i++) { + ret = rzv2m_i2c_master_xfer1(priv, &msgs[i], i == (num - 1)); + if (ret < 0) + goto out; + } + ret = num; + +out: + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + + return ret; +} + +static u32 rzv2m_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | + I2C_FUNC_10BIT_ADDR; +} + +static const struct i2c_adapter_quirks rzv2m_i2c_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN, +}; + +static struct i2c_algorithm rzv2m_i2c_algo = { + .master_xfer = rzv2m_i2c_master_xfer, + .functionality = rzv2m_i2c_func, +}; + +static int rzv2m_i2c_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct rzv2m_i2c_priv *priv; + struct reset_control *rstc; + struct i2c_adapter *adap; + struct resource *res; + int irq, ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(priv->base)) + return PTR_ERR(priv->base); + + priv->clk = devm_clk_get(dev, NULL); + if (IS_ERR(priv->clk)) + return dev_err_probe(dev, PTR_ERR(priv->clk), "Can't get clock\n"); + + rstc = devm_reset_control_get_shared(dev, NULL); + if (IS_ERR(rstc)) + return dev_err_probe(dev, PTR_ERR(rstc), "Missing reset ctrl\n"); + /* + * The reset also affects other HW that is not under the control + * of Linux. Therefore, all we can do is deassert the reset. + */ + reset_control_deassert(rstc); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + ret = devm_request_irq(dev, irq, rzv2m_i2c_tia_irq_handler, 0, + dev_name(dev), priv); + if (ret < 0) + return dev_err_probe(dev, ret, "Unable to request irq %d\n", irq); + + adap = &priv->adap; + adap->nr = pdev->id; + adap->algo = &rzv2m_i2c_algo; + adap->quirks = &rzv2m_i2c_quirks; + adap->class = I2C_CLASS_DEPRECATED; + adap->dev.parent = dev; + adap->owner = THIS_MODULE; + device_set_node(&adap->dev, dev_fwnode(dev)); + i2c_set_adapdata(adap, priv); + strscpy(adap->name, pdev->name, sizeof(adap->name)); + init_completion(&priv->msg_tia_done); + + ret = rzv2m_i2c_clock_calculate(dev, priv); + if (ret < 0) + return ret; + + pm_runtime_enable(dev); + + pm_runtime_get_sync(dev); + rzv2m_i2c_init(priv); + pm_runtime_put(dev); + + platform_set_drvdata(pdev, priv); + + ret = i2c_add_numbered_adapter(adap); + if (ret < 0) + pm_runtime_disable(dev); + + return ret; +} + +static int rzv2m_i2c_remove(struct platform_device *pdev) +{ + struct rzv2m_i2c_priv *priv = platform_get_drvdata(pdev); + struct device *dev = priv->adap.dev.parent; + + i2c_del_adapter(&priv->adap); + bit_clrl(priv->base + IICB0CTL0, IICB0IICE); + pm_runtime_disable(dev); + + return 0; +} + +static int rzv2m_i2c_suspend(struct device *dev) +{ + struct rzv2m_i2c_priv *priv = dev_get_drvdata(dev); + int ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) + return ret; + + bit_clrl(priv->base + IICB0CTL0, IICB0IICE); + pm_runtime_put(dev); + + return 0; +} + +static int rzv2m_i2c_resume(struct device *dev) +{ + struct rzv2m_i2c_priv *priv = dev_get_drvdata(dev); + int ret; + + ret = rzv2m_i2c_clock_calculate(dev, priv); + if (ret < 0) + return ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) + return ret; + + rzv2m_i2c_init(priv); + pm_runtime_put(dev); + + return 0; +} + +static const struct of_device_id rzv2m_i2c_ids[] = { + { .compatible = "renesas,rzv2m-i2c" }, + { } +}; +MODULE_DEVICE_TABLE(of, rzv2m_i2c_ids); + +static const struct dev_pm_ops rzv2m_i2c_pm_ops = { + SYSTEM_SLEEP_PM_OPS(rzv2m_i2c_suspend, rzv2m_i2c_resume) +}; + +static struct platform_driver rzv2m_i2c_driver = { + .driver = { + .name = "rzv2m-i2c", + .of_match_table = rzv2m_i2c_ids, + .pm = pm_sleep_ptr(&rzv2m_i2c_pm_ops), + }, + .probe = rzv2m_i2c_probe, + .remove = rzv2m_i2c_remove, +}; +module_platform_driver(rzv2m_i2c_driver); + +MODULE_DESCRIPTION("RZ/V2M I2C bus driver"); +MODULE_AUTHOR("Renesas Electronics Corporation"); +MODULE_LICENSE("GPL");