[PATCH 2/3] media: platform: meson: Add Amlogic Meson G12A AO CEC Controller driver

From: Neil Armstrong
Date: Mon Mar 25 2019 - 13:35:25 EST

The Amlogic G12A SoC embeds a second CEC controller with a totally
different design.

The two controller can work in the same time since the CEC line can
be set to two different pins on the two controllers.

This second CEC controller is documented as "AO-CEC-B", thus the
registers will be named "CECB_" to differenciate with the other
AO-CEC driver.

Unlike the other AO-CEC controller, this one takes the Oscillator
clock as input and embeds a dual-divider to provide a precise
32768Hz clock for communication. This is handled by registering
a clock in the driver.

Unlike the other AO-CEC controller, this controller supports setting
up to 15 logical adresses and supports the signal_free_time settings
in the transmit function.

Unfortunately, this controller does not support "monitor" mode.

Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
---
drivers/media/platform/Kconfig | 13 +
drivers/media/platform/meson/Makefile | 1 +
drivers/media/platform/meson/ao-cec-g12a.c | 783 +++++++++++++++++++++
3 files changed, 797 insertions(+)
create mode 100644 drivers/media/platform/meson/ao-cec-g12a.c

diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
index 4acbed189644..92ea07ddc609 100644
--- a/drivers/media/platform/Kconfig
+++ b/drivers/media/platform/Kconfig
@@ -578,6 +578,19 @@ config VIDEO_MESON_AO_CEC
generic CEC framework interface.
CEC bus is present in the HDMI connector and enables communication

+config VIDEO_MESON_G12A_AO_CEC
+ tristate "Amlogic Meson G12A AO CEC driver"
+ depends on ARCH_MESON || COMPILE_TEST
+ select CEC_CORE
+ select CEC_NOTIFIER
+ ---help---
+ This is a driver for Amlogic Meson G12A SoCs AO CEC interface.
+ This driver if for the new AO-CEC module found in G12A SoCs,
+ usually named AO_CEC_B in documentation.
+ It uses the generic CEC framework interface.
+ CEC bus is present in the HDMI connector and enables communication
+ between compatible devices.
+
config CEC_GPIO
tristate "Generic GPIO-based CEC driver"
depends on PREEMPT || COMPILE_TEST
diff --git a/drivers/media/platform/meson/Makefile b/drivers/media/platform/meson/Makefile
index 597beb8f34d1..f611c23c3718 100644
--- a/drivers/media/platform/meson/Makefile
+++ b/drivers/media/platform/meson/Makefile
@@ -1 +1,2 @@
obj-$(CONFIG_VIDEO_MESON_AO_CEC) += ao-cec.o
+obj-$(CONFIG_VIDEO_MESON_G12A_AO_CEC) += ao-cec-g12a.o
diff --git a/drivers/media/platform/meson/ao-cec-g12a.c b/drivers/media/platform/meson/ao-cec-g12a.c
new file mode 100644
index 000000000000..8977ae994164
--- /dev/null
+++ b/drivers/media/platform/meson/ao-cec-g12a.c
@@ -0,0 +1,783 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Driver for Amlogic Meson AO CEC G12A Controller
+ *
+ * Copyright (C) 2017 Amlogic, Inc. All rights reserved
+ * Copyright (C) 2019 BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/regmap.h>
+#include <media/cec.h>
+#include <media/cec-notifier.h>
+#include <linux/clk-provider.h>
+
+/* CEC Registers */
+
+#define CECB_CLK_CNTL_REG0 0x00
+
+#define CECB_CLK_CNTL_N1 GENMASK(11, 0)
+#define CECB_CLK_CNTL_N2 GENMASK(23, 12)
+#define CECB_CLK_CNTL_DUAL_EN BIT(28)
+#define CECB_CLK_CNTL_OUTPUT_EN BIT(30)
+#define CECB_CLK_CNTL_INPUT_EN BIT(31)
+
+#define CECB_CLK_CNTL_REG1 0x04
+
+#define CECB_CLK_CNTL_M1 GENMASK(11, 0)
+#define CECB_CLK_CNTL_M2 GENMASK(23, 12)
+#define CECB_CLK_CNTL_BYPASS_EN BIT(24)
+
+/*
+ * [14:12] Filter_del. For glitch-filtering CEC line, ignore signal
+ * change pulse width < filter_del * T(filter_tick) * 3.
+ * [9:8] Filter_tick_sel: Select which periodical pulse for
+ * glitch-filtering CEC line signal.
+ * - 0=Use T(xtal)*3 = 125ns;
+ * - 1=Use once-per-1us pulse;
+ * - 2=Use once-per-10us pulse;
+ * - 3=Use once-per-100us pulse.
+ * [3] Sysclk_en. 0=Disable system clock; 1=Enable system clock.
+ * [2:1] cntl_clk
+ * - 0 = Disable clk (Power-off mode)
+ * - 1 = Enable gated clock (Normal mode)
+ * - 2 = Enable free-run clk (Debug mode)
+ * [0] SW_RESET 1=Apply reset; 0=No reset.
+ */
+#define CECB_GEN_CNTL_REG 0x08
+
+#define CECB_GEN_CNTL_RESET BIT(0)
+#define CECB_GEN_CNTL_CLK_DISABLE 0
+#define CECB_GEN_CNTL_CLK_ENABLE 1
+#define CECB_GEN_CNTL_CLK_ENABLE_DBG 2
+#define CECB_GEN_CNTL_CLK_CTRL_MASK GENMASK(2, 1)
+#define CECB_GEN_CNTL_SYS_CLK_EN BIT(3)
+#define CECB_GEN_CNTL_FILTER_TICK_125NS 0
+#define CECB_GEN_CNTL_FILTER_TICK_1US 1
+#define CECB_GEN_CNTL_FILTER_TICK_10US 2
+#define CECB_GEN_CNTL_FILTER_TICK_100US 3
+#define CECB_GEN_CNTL_FILTER_TICK_SEL GENMASK(9, 8)
+#define CECB_GEN_CNTL_FILTER_DEL GENMASK(14, 12)
+
+/*
+ * [7:0] cec_reg_addr
+ * [15:8] cec_reg_wrdata
+ * [16] cec_reg_wr
+ * - 0 = Read
+ * - 1 = Write
+ * [31:24] cec_reg_rddata
+ */
+#define CECB_RW_REG 0x0c
+
+#define CECB_RW_ADDR GENMASK(7, 0)
+#define CECB_RW_WR_DATA GENMASK(15, 8)
+#define CECB_RW_WRITE_EN BIT(16)
+#define CECB_RW_BUS_BUSY BIT(23)
+#define CECB_RW_RD_DATA GENMASK(31, 24)
+
+/*
+ * [0] DONE Interrupt
+ * [1] End Of Message Interrupt
+ * [2] Not Acknowlegde Interrupt
+ * [3] Arbitration Loss Interrupt
+ * [4] Initiator Error Interrupt
+ * [5] Follower Error Interrupt
+ * [6] Wake-Up Interrupt
+ */
+#define CECB_INTR_MASKN_REG 0x10
+#define CECB_INTR_CLR_REG 0x14
+#define CECB_INTR_STAT_REG 0x18
+
+#define CECB_INTR_DONE BIT(0)
+#define CECB_INTR_EOM BIT(1)
+#define CECB_INTR_NACK BIT(2)
+#define CECB_INTR_ARB_LOSS BIT(3)
+#define CECB_INTR_INITIATOR_ERR BIT(4)
+#define CECB_INTR_FOLLOWER_ERR BIT(5)
+#define CECB_INTR_WAKE_UP BIT(6)
+
+/* CEC Commands */
+
+#define CECB_CTRL 0x00
+
+#define CECB_CTRL_SEND BIT(0)
+#define CECB_CTRL_TYPE GENMASK(2, 1)
+#define CECB_CTRL_TYPE_RETRY 0
+#define CECB_CTRL_TYPE_NEW 1
+#define CECB_CTRL_TYPE_NEXT 2
+
+#define CECB_CTRL2 0x01
+#define CECB_INTR_MASK 0x02
+#define CECB_LADD_LOW 0x05
+#define CECB_LADD_HIGH 0x06
+#define CECB_TX_CNT 0x07
+#define CECB_RX_CNT 0x08
+#define CECB_STAT0 0x09
+#define CECB_TX_DATA00 0x10
+#define CECB_TX_DATA01 0x11
+#define CECB_TX_DATA02 0x12
+#define CECB_TX_DATA03 0x13
+#define CECB_TX_DATA04 0x14
+#define CECB_TX_DATA05 0x15
+#define CECB_TX_DATA06 0x16
+#define CECB_TX_DATA07 0x17
+#define CECB_TX_DATA08 0x18
+#define CECB_TX_DATA09 0x19
+#define CECB_TX_DATA10 0x1A
+#define CECB_TX_DATA11 0x1B
+#define CECB_TX_DATA12 0x1C
+#define CECB_TX_DATA13 0x1D
+#define CECB_TX_DATA14 0x1E
+#define CECB_TX_DATA15 0x1F
+#define CECB_RX_DATA00 0x20
+#define CECB_RX_DATA01 0x21
+#define CECB_RX_DATA02 0x22
+#define CECB_RX_DATA03 0x23
+#define CECB_RX_DATA04 0x24
+#define CECB_RX_DATA05 0x25
+#define CECB_RX_DATA06 0x26
+#define CECB_RX_DATA07 0x27
+#define CECB_RX_DATA08 0x28
+#define CECB_RX_DATA09 0x29
+#define CECB_RX_DATA10 0x2A
+#define CECB_RX_DATA11 0x2B
+#define CECB_RX_DATA12 0x2C
+#define CECB_RX_DATA13 0x2D
+#define CECB_RX_DATA14 0x2E
+#define CECB_RX_DATA15 0x2F
+#define CECB_LOCK_BUF 0x30
+
+#define CECB_LOCK_BUF_EN BIT(0)
+
+#define CECB_WAKEUPCTRL 0x31
+
+struct meson_ao_cec_g12a_device {
+ struct platform_device *pdev;
+ struct regmap *regmap;
+ struct regmap *regmap_cec;
+ spinlock_t cec_reg_lock;
+ struct cec_notifier *notify;
+ struct cec_adapter *adap;
+ struct cec_msg rx_msg;
+ struct clk *oscin;
+ struct clk *core;
+};
+
+static const struct regmap_config meson_ao_cec_g12a_regmap_conf = {
+ .reg_bits = 8,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = CECB_INTR_STAT_REG,
+};
+
+/*
+ * The AO-CECB embeds a dual/divider to generate a more precise
+ * 32,768KHz clock for CEC core clock.
+ * ______ ______
+ * | | | |
+ * ______ | Div1 |-| Cnt1 | ______
+ * | | /|______| |______|\ | |
+ * Xtal-->| Gate |---| ______ ______ X-X--| Gate |-->
+ * |______| | \| | | |/ | |______|
+ * | | Div2 |-| Cnt2 | |
+ * | |______| |______| |
+ * |_______________________|
+ *
+ * The dividing can be switched to single or dual, with a counter
+ * for each divider to set when the switching is done.
+ * The entire dividing mechanism can be also bypassed.
+ */
+
+struct meson_ao_cec_g12a_dualdiv_clk {
+ struct clk_hw hw;
+ struct regmap *regmap;
+};
+
+#define hw_to_meson_ao_cec_g12a_dualdiv_clk(_hw) \
+ container_of(_hw, struct meson_ao_cec_g12a_dualdiv_clk, hw) \
+
+static unsigned long
+meson_ao_cec_g12a_dualdiv_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct meson_ao_cec_g12a_dualdiv_clk *dualdiv_clk =
+ hw_to_meson_ao_cec_g12a_dualdiv_clk(hw);
+ unsigned long n1;
+ u32 reg0, reg1;
+
+ regmap_read(dualdiv_clk->regmap, CECB_CLK_CNTL_REG0, &reg0);
+ regmap_read(dualdiv_clk->regmap, CECB_CLK_CNTL_REG0, &reg1);
+
+ if (reg1 & CECB_CLK_CNTL_BYPASS_EN)
+ return parent_rate;
+
+ if (reg0 & CECB_CLK_CNTL_DUAL_EN) {
+ unsigned long n2, m1, m2, f1, f2, p1, p2;
+
+ n1 = FIELD_GET(CECB_CLK_CNTL_N1, reg0) + 1;
+ n2 = FIELD_GET(CECB_CLK_CNTL_N2, reg0) + 1;
+
+ m1 = FIELD_GET(CECB_CLK_CNTL_M1, reg1) + 1;
+ m2 = FIELD_GET(CECB_CLK_CNTL_M1, reg1) + 1;
+
+ f1 = DIV_ROUND_CLOSEST(parent_rate, n1);
+ f2 = DIV_ROUND_CLOSEST(parent_rate, n2);
+
+ p1 = DIV_ROUND_CLOSEST(100000000 * m1, f1 * (m1 + m2));
+ p2 = DIV_ROUND_CLOSEST(100000000 * m2, f2 * (m1 + m2));
+
+ return DIV_ROUND_UP(100000000, p1 + p2);
+ }
+
+ n1 = FIELD_GET(CECB_CLK_CNTL_N1, reg0) + 1;
+
+ return DIV_ROUND_CLOSEST(parent_rate, n1);
+}
+
+static int meson_ao_cec_g12a_dualdiv_clk_enable(struct clk_hw *hw)
+{
+ struct meson_ao_cec_g12a_dualdiv_clk *dualdiv_clk =
+ hw_to_meson_ao_cec_g12a_dualdiv_clk(hw);
+
+
+ /* Disable Input & Output */
+ regmap_update_bits(dualdiv_clk->regmap, CECB_CLK_CNTL_REG0,
+ CECB_CLK_CNTL_INPUT_EN | CECB_CLK_CNTL_OUTPUT_EN,
+ 0);
+
+ /* Set N1 & N2 */
+ regmap_update_bits(dualdiv_clk->regmap, CECB_CLK_CNTL_REG0,
+ CECB_CLK_CNTL_N1,
+ FIELD_PREP(CECB_CLK_CNTL_N1, 733 - 1));
+
+ regmap_update_bits(dualdiv_clk->regmap, CECB_CLK_CNTL_REG0,
+ CECB_CLK_CNTL_N2,
+ FIELD_PREP(CECB_CLK_CNTL_N2, 732 - 1));
+
+ /* Set M1 & M2 */
+ regmap_update_bits(dualdiv_clk->regmap, CECB_CLK_CNTL_REG1,
+ CECB_CLK_CNTL_M1,
+ FIELD_PREP(CECB_CLK_CNTL_M1, 8 - 1));
+
+ regmap_update_bits(dualdiv_clk->regmap, CECB_CLK_CNTL_REG1,
+ CECB_CLK_CNTL_M2,
+ FIELD_PREP(CECB_CLK_CNTL_M2, 11 - 1));
+
+ /* Enable Dual divisor */
+ regmap_update_bits(dualdiv_clk->regmap, CECB_CLK_CNTL_REG0,
+ CECB_CLK_CNTL_DUAL_EN, CECB_CLK_CNTL_DUAL_EN);
+
+ /* Disable divisor bypass */
+ regmap_update_bits(dualdiv_clk->regmap, CECB_CLK_CNTL_REG1,
+ CECB_CLK_CNTL_BYPASS_EN, 0);
+
+ /* Enable Input & Output */
+ regmap_update_bits(dualdiv_clk->regmap, CECB_CLK_CNTL_REG0,
+ CECB_CLK_CNTL_INPUT_EN | CECB_CLK_CNTL_OUTPUT_EN,
+ CECB_CLK_CNTL_INPUT_EN | CECB_CLK_CNTL_OUTPUT_EN);
+
+ return 0;
+}
+
+static void meson_ao_cec_g12a_dualdiv_clk_disable(struct clk_hw *hw)
+{
+ struct meson_ao_cec_g12a_dualdiv_clk *dualdiv_clk =
+ hw_to_meson_ao_cec_g12a_dualdiv_clk(hw);
+
+ regmap_update_bits(dualdiv_clk->regmap, CECB_CLK_CNTL_REG0,
+ CECB_CLK_CNTL_INPUT_EN | CECB_CLK_CNTL_OUTPUT_EN,
+ 0);
+}
+
+static int meson_ao_cec_g12a_dualdiv_clk_is_enabled(struct clk_hw *hw)
+{
+ struct meson_ao_cec_g12a_dualdiv_clk *dualdiv_clk =
+ hw_to_meson_ao_cec_g12a_dualdiv_clk(hw);
+ int val;
+
+ regmap_read(dualdiv_clk->regmap, CECB_CLK_CNTL_REG0, &val);
+
+ return !!(val & (CECB_CLK_CNTL_INPUT_EN | CECB_CLK_CNTL_OUTPUT_EN));
+}
+
+static const struct clk_ops meson_ao_cec_g12a_dualdiv_clk_ops = {
+ .recalc_rate = meson_ao_cec_g12a_dualdiv_clk_recalc_rate,
+ .is_enabled = meson_ao_cec_g12a_dualdiv_clk_is_enabled,
+ .enable = meson_ao_cec_g12a_dualdiv_clk_enable,
+ .disable = meson_ao_cec_g12a_dualdiv_clk_disable,
+};
+
+static int meson_ao_cec_g12a_setup_clk(struct meson_ao_cec_g12a_device *ao_cec)
+{
+ struct meson_ao_cec_g12a_dualdiv_clk *dualdiv_clk;
+ struct device *dev = &ao_cec->pdev->dev;
+ struct clk_init_data init;
+ const char *parent_name;
+ struct clk *clk;
+ char *name;
+
+ dualdiv_clk = devm_kzalloc(dev, sizeof(*dualdiv_clk), GFP_KERNEL);
+ if (!dualdiv_clk)
+ return -ENOMEM;
+
+ name = kasprintf(GFP_KERNEL, "%s#dualdiv_clk", dev_name(dev));
+ if (!name)
+ return -ENOMEM;
+
+ parent_name = __clk_get_name(ao_cec->oscin);
+
+ init.name = name;
+ init.ops = &meson_ao_cec_g12a_dualdiv_clk_ops;
+ init.flags = 0;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+ dualdiv_clk->regmap = ao_cec->regmap;
+ dualdiv_clk->hw.init = &init;
+
+ clk = devm_clk_register(dev, &dualdiv_clk->hw);
+ kfree(name);
+ if (IS_ERR(clk)) {
+ dev_err(dev, "failed to register clock\n");
+ return PTR_ERR(clk);
+ }
+
+ ao_cec->core = clk;
+
+ return 0;
+}
+
+static int meson_ao_cec_g12a_read(void *context, unsigned int addr,
+ unsigned int *data)
+{
+ struct meson_ao_cec_g12a_device *ao_cec = context;
+ u32 reg = FIELD_PREP(CECB_RW_ADDR, addr);
+ unsigned long flags;
+ int ret = 0;
+
+ spin_lock_irqsave(&ao_cec->cec_reg_lock, flags);
+
+ ret = regmap_write(ao_cec->regmap, CECB_RW_REG, reg);
+
+ ret = regmap_read_poll_timeout(ao_cec->regmap, CECB_RW_REG, reg,
+ !(reg & CECB_RW_BUS_BUSY),
+ 5, 1000);
+ if (ret)
+ goto read_out;
+
+ ret = regmap_read(ao_cec->regmap, CECB_RW_REG, &reg);
+
+ *data = FIELD_GET(CECB_RW_RD_DATA, reg);
+
+read_out:
+ spin_unlock_irqrestore(&ao_cec->cec_reg_lock, flags);
+
+ return ret;
+}
+
+static int meson_ao_cec_g12a_write(void *context, unsigned int addr,
+ unsigned int data)
+{
+ struct meson_ao_cec_g12a_device *ao_cec = context;
+ unsigned long flags;
+ u32 reg = FIELD_PREP(CECB_RW_ADDR, addr) |
+ FIELD_PREP(CECB_RW_WR_DATA, data) |
+ CECB_RW_WRITE_EN;
+ int ret = 0;
+
+ spin_lock_irqsave(&ao_cec->cec_reg_lock, flags);
+
+ ret = regmap_write(ao_cec->regmap, CECB_RW_REG, reg);
+
+ spin_unlock_irqrestore(&ao_cec->cec_reg_lock, flags);
+
+ return ret;
+}
+
+static const struct regmap_config meson_ao_cec_g12a_cec_regmap_conf = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .reg_read = meson_ao_cec_g12a_read,
+ .reg_write = meson_ao_cec_g12a_write,
+ .max_register = 0xffff,
+ .fast_io = true,
+};
+
+static inline void
+meson_ao_cec_g12a_irq_setup(struct meson_ao_cec_g12a_device *ao_cec,
+ bool enable)
+{
+ u32 cfg = CECB_INTR_DONE | CECB_INTR_EOM | CECB_INTR_NACK |
+ CECB_INTR_ARB_LOSS | CECB_INTR_INITIATOR_ERR |
+ CECB_INTR_FOLLOWER_ERR;
+
+ regmap_write(ao_cec->regmap, CECB_INTR_MASKN_REG,
+ enable ? cfg : 0);
+}
+
+static void meson_ao_cec_g12a_irq_rx(struct meson_ao_cec_g12a_device *ao_cec)
+{
+ int i, ret = 0;
+ u32 val;
+
+ ret = regmap_read(ao_cec->regmap_cec, CECB_RX_CNT, &val);
+
+ ao_cec->rx_msg.len = val;
+ if (ao_cec->rx_msg.len > CEC_MAX_MSG_SIZE)
+ ao_cec->rx_msg.len = CEC_MAX_MSG_SIZE;
+
+ for (i = 0; i < ao_cec->rx_msg.len; i++) {
+ ret |= regmap_read(ao_cec->regmap_cec,
+ CECB_RX_DATA00 + i, &val);
+
+ ao_cec->rx_msg.msg[i] = val & 0xff;
+ }
+
+ ret |= regmap_write(ao_cec->regmap_cec, CECB_LOCK_BUF, 0);
+ if (ret)
+ return;
+
+ cec_received_msg(ao_cec->adap, &ao_cec->rx_msg);
+}
+
+static irqreturn_t meson_ao_cec_g12a_irq(int irq, void *data)
+{
+ struct meson_ao_cec_g12a_device *ao_cec = data;
+ u32 stat;
+
+ regmap_read(ao_cec->regmap, CECB_INTR_STAT_REG, &stat);
+ if (stat)
+ return IRQ_WAKE_THREAD;
+
+ return IRQ_NONE;
+}
+
+static irqreturn_t meson_ao_cec_g12a_irq_thread(int irq, void *data)
+{
+ struct meson_ao_cec_g12a_device *ao_cec = data;
+ u32 stat;
+
+ regmap_read(ao_cec->regmap, CECB_INTR_STAT_REG, &stat);
+ regmap_write(ao_cec->regmap, CECB_INTR_CLR_REG, stat);
+
+ if (stat & CECB_INTR_DONE)
+ cec_transmit_attempt_done(ao_cec->adap, CEC_TX_STATUS_OK);
+
+ if (stat & CECB_INTR_EOM)
+ meson_ao_cec_g12a_irq_rx(ao_cec);
+
+ if (stat & CECB_INTR_NACK)
+ cec_transmit_attempt_done(ao_cec->adap, CEC_TX_STATUS_NACK);
+
+ if (stat & CECB_INTR_ARB_LOSS) {
+ regmap_write(ao_cec->regmap_cec, CECB_TX_CNT, 0);
+ regmap_update_bits(ao_cec->regmap_cec, CECB_CTRL,
+ CECB_CTRL_SEND | CECB_CTRL_TYPE, 0);
+ cec_transmit_attempt_done(ao_cec->adap, CEC_TX_STATUS_ARB_LOST);
+ }
+
+ if (stat & CECB_INTR_INITIATOR_ERR)
+ cec_transmit_attempt_done(ao_cec->adap, CEC_TX_STATUS_NACK);
+
+ if (stat & CECB_INTR_FOLLOWER_ERR) {
+ regmap_write(ao_cec->regmap_cec, CECB_LOCK_BUF, 0);
+ cec_transmit_attempt_done(ao_cec->adap, CEC_TX_STATUS_NACK);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int
+meson_ao_cec_g12a_set_log_addr(struct cec_adapter *adap, u8 logical_addr)
+{
+ struct meson_ao_cec_g12a_device *ao_cec = adap->priv;
+ int ret = 0;
+
+ if (logical_addr == CEC_LOG_ADDR_INVALID) {
+ ret = regmap_write(ao_cec->regmap_cec, CECB_LADD_LOW, 0);
+ ret = regmap_write(ao_cec->regmap_cec, CECB_LADD_HIGH, 0);
+ } else if (logical_addr < 8) {
+ ret = regmap_update_bits(ao_cec->regmap_cec, CECB_LADD_LOW,
+ BIT(logical_addr),
+ BIT(logical_addr));
+ } else {
+ ret = regmap_update_bits(ao_cec->regmap_cec, CECB_LADD_HIGH,
+ BIT(logical_addr - 8),
+ BIT(logical_addr - 8));
+ }
+
+ /* Always set Broadcast/Unregistered 15 address */
+ ret |= regmap_update_bits(ao_cec->regmap_cec, CECB_LADD_HIGH,
+ BIT(CEC_LOG_ADDR_UNREGISTERED - 8),
+ BIT(CEC_LOG_ADDR_UNREGISTERED - 8));
+
+ return ret;
+}
+
+static int meson_ao_cec_g12a_transmit(struct cec_adapter *adap, u8 attempts,
+ u32 signal_free_time, struct cec_msg *msg)
+{
+ struct meson_ao_cec_g12a_device *ao_cec = adap->priv;
+ unsigned int type;
+ int ret = 0;
+ u32 val;
+ int i;
+
+ /* Check if RX is in progress */
+ ret = regmap_read(ao_cec->regmap_cec, CECB_LOCK_BUF, &val);
+ if (ret)
+ return ret;
+ if (val & CECB_LOCK_BUF_EN)
+ return -EBUSY;
+
+ /* Check if TX Busy */
+ ret = regmap_read(ao_cec->regmap_cec, CECB_CTRL, &val);
+ if (ret)
+ return ret;
+ if (val & CECB_CTRL_SEND)
+ return -EBUSY;
+
+ switch (signal_free_time) {
+ case CEC_SIGNAL_FREE_TIME_RETRY:
+ type = CECB_CTRL_TYPE_RETRY;
+ break;
+ case CEC_SIGNAL_FREE_TIME_NEXT_XFER:
+ type = CECB_CTRL_TYPE_NEXT;
+ break;
+ case CEC_SIGNAL_FREE_TIME_NEW_INITIATOR:
+ default:
+ type = CECB_CTRL_TYPE_NEW;
+ break;
+ }
+
+ for (i = 0; i < msg->len; i++)
+ ret |= regmap_write(ao_cec->regmap_cec, CECB_TX_DATA00 + i,
+ msg->msg[i]);
+
+ ret |= regmap_write(ao_cec->regmap_cec, CECB_TX_CNT, msg->len);
+ ret = regmap_update_bits(ao_cec->regmap_cec, CECB_CTRL,
+ CECB_CTRL_SEND |
+ CECB_CTRL_TYPE,
+ CECB_CTRL_SEND |
+ FIELD_PREP(CECB_CTRL_TYPE, type));
+
+ return ret;
+}
+
+static int meson_ao_cec_g12a_adap_enable(struct cec_adapter *adap, bool enable)
+{
+ struct meson_ao_cec_g12a_device *ao_cec = adap->priv;
+
+ meson_ao_cec_g12a_irq_setup(ao_cec, false);
+
+ regmap_update_bits(ao_cec->regmap, CECB_GEN_CNTL_REG,
+ CECB_GEN_CNTL_RESET, CECB_GEN_CNTL_RESET);
+
+ if (!enable)
+ return 0;
+
+ /* Setup Filter */
+ regmap_update_bits(ao_cec->regmap, CECB_GEN_CNTL_REG,
+ CECB_GEN_CNTL_FILTER_TICK_SEL |
+ CECB_GEN_CNTL_FILTER_DEL,
+ FIELD_PREP(CECB_GEN_CNTL_FILTER_TICK_SEL,
+ CECB_GEN_CNTL_FILTER_TICK_1US) |
+ FIELD_PREP(CECB_GEN_CNTL_FILTER_DEL, 7));
+
+ /* Enable System Clock */
+ regmap_update_bits(ao_cec->regmap, CECB_GEN_CNTL_REG,
+ CECB_GEN_CNTL_SYS_CLK_EN,
+ CECB_GEN_CNTL_SYS_CLK_EN);
+
+ /* Enable gated clock (Normal mode). */
+ regmap_update_bits(ao_cec->regmap, CECB_GEN_CNTL_REG,
+ CECB_GEN_CNTL_CLK_CTRL_MASK,
+ FIELD_PREP(CECB_GEN_CNTL_CLK_CTRL_MASK,
+ CECB_GEN_CNTL_CLK_ENABLE));
+
+ /* Release Reset */
+ regmap_update_bits(ao_cec->regmap, CECB_GEN_CNTL_REG,
+ CECB_GEN_CNTL_RESET, 0);
+
+ meson_ao_cec_g12a_irq_setup(ao_cec, true);
+
+ return 0;
+}
+
+static const struct cec_adap_ops meson_ao_cec_g12a_ops = {
+ .adap_enable = meson_ao_cec_g12a_adap_enable,
+ .adap_log_addr = meson_ao_cec_g12a_set_log_addr,
+ .adap_transmit = meson_ao_cec_g12a_transmit,
+};
+
+static int meson_ao_cec_g12a_probe(struct platform_device *pdev)
+{
+ struct meson_ao_cec_g12a_device *ao_cec;
+ struct platform_device *hdmi_dev;
+ struct device_node *np;
+ struct resource *res;
+ void __iomem *base;
+ int ret, irq;
+
+ np = of_parse_phandle(pdev->dev.of_node, "hdmi-phandle", 0);
+ if (!np) {
+ dev_err(&pdev->dev, "Failed to find hdmi node\n");
+ return -ENODEV;
+ }
+
+ hdmi_dev = of_find_device_by_node(np);
+ of_node_put(np);
+ if (hdmi_dev == NULL)
+ return -EPROBE_DEFER;
+
+ put_device(&hdmi_dev->dev);
+ ao_cec = devm_kzalloc(&pdev->dev, sizeof(*ao_cec), GFP_KERNEL);
+ if (!ao_cec)
+ return -ENOMEM;
+
+ spin_lock_init(&ao_cec->cec_reg_lock);
+ ao_cec->pdev = pdev;
+
+ ao_cec->notify = cec_notifier_get(&hdmi_dev->dev);
+ if (!ao_cec->notify)
+ return -ENOMEM;
+
+ ao_cec->adap = cec_allocate_adapter(&meson_ao_cec_g12a_ops, ao_cec,
+ "meson_g12a_ao_cec",
+ CEC_CAP_DEFAULTS,
+ CEC_MAX_LOG_ADDRS);
+ if (IS_ERR(ao_cec->adap)) {
+ ret = PTR_ERR(ao_cec->adap);
+ goto out_probe_notify;
+ }
+
+ ao_cec->adap->owner = THIS_MODULE;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(base)) {
+ ret = PTR_ERR(base);
+ goto out_probe_adapter;
+ }
+
+ ao_cec->regmap = devm_regmap_init_mmio(&pdev->dev, base,
+ &meson_ao_cec_g12a_regmap_conf);
+ if (IS_ERR(ao_cec->regmap)) {
+ ret = PTR_ERR(ao_cec->regmap);
+ goto out_probe_adapter;
+ }
+
+ ao_cec->regmap_cec = devm_regmap_init(&pdev->dev, NULL, ao_cec,
+ &meson_ao_cec_g12a_cec_regmap_conf);
+ if (IS_ERR(ao_cec->regmap_cec)) {
+ ret = PTR_ERR(ao_cec->regmap_cec);
+ goto out_probe_adapter;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ ret = devm_request_threaded_irq(&pdev->dev, irq,
+ meson_ao_cec_g12a_irq,
+ meson_ao_cec_g12a_irq_thread,
+ 0, NULL, ao_cec);
+ if (ret) {
+ dev_err(&pdev->dev, "irq request failed\n");
+ goto out_probe_adapter;
+ }
+
+ ao_cec->oscin = devm_clk_get(&pdev->dev, "oscin");
+ if (IS_ERR(ao_cec->oscin)) {
+ dev_err(&pdev->dev, "oscin clock request failed\n");
+ ret = PTR_ERR(ao_cec->oscin);
+ goto out_probe_adapter;
+ }
+
+ ret = meson_ao_cec_g12a_setup_clk(ao_cec);
+ if (ret)
+ goto out_probe_clk;
+
+ ret = clk_prepare_enable(ao_cec->core);
+ if (ret) {
+ dev_err(&pdev->dev, "core clock enable failed\n");
+ goto out_probe_clk;
+ }
+
+ device_reset_optional(&pdev->dev);
+
+ platform_set_drvdata(pdev, ao_cec);
+
+ ret = cec_register_adapter(ao_cec->adap, &pdev->dev);
+ if (ret < 0) {
+ cec_notifier_put(ao_cec->notify);
+ goto out_probe_core_clk;
+ }
+
+ /* Setup Hardware */
+ regmap_write(ao_cec->regmap, CECB_GEN_CNTL_REG, CECB_GEN_CNTL_RESET);
+
+ cec_register_cec_notifier(ao_cec->adap, ao_cec->notify);
+
+ return 0;
+
+out_probe_core_clk:
+ clk_disable_unprepare(ao_cec->core);
+
+out_probe_clk:
+ clk_disable_unprepare(ao_cec->oscin);
+
+out_probe_adapter:
+ cec_delete_adapter(ao_cec->adap);
+
+out_probe_notify:
+ cec_notifier_put(ao_cec->notify);
+
+ dev_err(&pdev->dev, "CEC controller registration failed\n");
+
+ return ret;
+}
+
+static int meson_ao_cec_g12a_remove(struct platform_device *pdev)
+{
+ struct meson_ao_cec_g12a_device *ao_cec = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(ao_cec->oscin);
+
+ cec_unregister_adapter(ao_cec->adap);
+
+ cec_notifier_put(ao_cec->notify);
+
+ return 0;
+}
+
+static const struct of_device_id meson_ao_cec_g12a_of_match[] = {
+ { .compatible = "amlogic,meson-g12a-ao-cec-b", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, meson_ao_cec_g12a_of_match);
+
+static struct platform_driver meson_ao_cec_g12a_driver = {
+ .probe = meson_ao_cec_g12a_probe,
+ .remove = meson_ao_cec_g12a_remove,
+ .driver = {
+ .name = "meson-ao-cec-g12a",
+ .of_match_table = of_match_ptr(meson_ao_cec_g12a_of_match),
+ },
+};
+
+module_platform_driver(meson_ao_cec_g12a_driver);
+
+MODULE_DESCRIPTION("Meson AO CEC G12A Controller driver");
+MODULE_AUTHOR("Neil Armstrong <narmstrong@xxxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
--
2.21.0