[PATCH 2/2] i3c: add driver for Renesas I3C controller
Frank Li
Frank.li at nxp.com
Tue Jul 15 08:04:32 PDT 2025
On Mon, Jul 14, 2025 at 11:12:09AM +0200, Wolfram Sang wrote:
Subject i3c: master: add ...
> This adds a basic driver for the I3C IP found in various SoCs like
kernel doc submitting-patches.rst suggest use imperative mood.
> RZ/G3S and G3E. Missing features to be added incrementally are IBI,
> HotJoin and target support. Other than that, this driver has been tested
> with I3C pure busses (2 targets) and mixed busses (2 I3C + various I2C
> targets). DAA and reading/writing to the temperature sensors worked
> reliably at different speeds.
Suggest commit message:
i3c: master: Add basic driver for Renesas RZ/G3S and G3E SoCs
Add a basic I3C master driver for the I3C controller found in Renesas
RZ/G3S and G3E SoCs. Support I3C pure busses (tested with two targets) and
mixed busses (two I3C devices plus various I2C targets). DAA and
communication with temperature sensors worked reliably at various speeds
Missing features such as IBI, HotJoin, and target mode will be added
incrementally.
>
> Signed-off-by: Wolfram Sang <wsa+renesas at sang-engineering.com>
> ---
>
> Changes since RFC:
> * updated #defines for registers (add extra indentation for bit
> definitions, use FIELD_* helpers)
> * switched to new I3C FIFO access helpers
> * removed unnecessary second filling of the FIFO before transfer
> * added INCBA handling again, so broadcast address is properly prepended
> to messages again
> * updated the list of supported CCCs
> * add 'unsupported CCC' error of the internal state machine
> * added renesas_i3c_wait_xfer() helper to ensure proper usage of
> wait_for_completion_timeout()
> * refactored 'i3c_reg_update' to match other 'i3c_reg*' helper arguments
> * renamed some functions to have the "renesas_" prefix
> * use scope_guard consistently when handling the xferqueue
> * do not activate interrupts we don't handle anymore
> * removed left over code which used rx_isr during DAA. This is not
> needed anymore
> * handled a race condition between rx_isr and resp_isr by expicitly
> checking in resp_isr if rx_isr has run already
> * less output in probe()
> * corrected some variable types
>
>
> MAINTAINERS | 7 +
> drivers/i3c/master/Kconfig | 10 +
> drivers/i3c/master/Makefile | 1 +
> drivers/i3c/master/renesas-i3c.c | 1433 ++++++++++++++++++++++++++++++
> 4 files changed, 1451 insertions(+)
> create mode 100644 drivers/i3c/master/renesas-i3c.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 60bba48f5479..6c841aa52113 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -11462,6 +11462,13 @@ S: Maintained
> F: Documentation/devicetree/bindings/i3c/cdns,i3c-master.yaml
> F: drivers/i3c/master/i3c-master-cdns.c
>
> +I3C DRIVER FOR RENESAS
> +M: Wolfram Sang <wsa+renesas at sang-engineering.com>
> +M: Tommaso Merciai <tommaso.merciai.xr at bp.renesas.com>
> +S: Supported
> +F: Documentation/devicetree/bindings/i3c/renesas,i3c.yaml
> +F: drivers/i3c/master/renesas-i3c.c
Add i3c mail list?
> +
> I3C DRIVER FOR SYNOPSYS DESIGNWARE
> S: Orphan
> F: Documentation/devicetree/bindings/i3c/snps,dw-i3c-master.yaml
> diff --git a/drivers/i3c/master/Kconfig b/drivers/i3c/master/Kconfig
> index 7b30db3253af..13df2944f2ec 100644
> --- a/drivers/i3c/master/Kconfig
> +++ b/drivers/i3c/master/Kconfig
> @@ -64,3 +64,13 @@ config MIPI_I3C_HCI_PCI
>
> This driver can also be built as a module. If so, the module will be
> called mipi-i3c-hci-pci.
> +
> +config RENESAS_I3C
> + tristate "Renesas I3C controller driver"
> + depends on HAS_IOMEM
> + depends on ARCH_RENESAS || COMPILE_TEST
> + help
> + Support the Renesas I3C controller as found in some RZ variants.
> +
> + This driver can also be built as a module. If so, the module will be
> + called renesas-i3c.
> diff --git a/drivers/i3c/master/Makefile b/drivers/i3c/master/Makefile
> index 3e97960160bc..aac74f3e3851 100644
> --- a/drivers/i3c/master/Makefile
> +++ b/drivers/i3c/master/Makefile
> @@ -4,3 +4,4 @@ obj-$(CONFIG_DW_I3C_MASTER) += dw-i3c-master.o
> obj-$(CONFIG_AST2600_I3C_MASTER) += ast2600-i3c-master.o
> obj-$(CONFIG_SVC_I3C_MASTER) += svc-i3c-master.o
> obj-$(CONFIG_MIPI_I3C_HCI) += mipi-i3c-hci/
> +obj-$(CONFIG_RENESAS_I3C) += renesas-i3c.o
> diff --git a/drivers/i3c/master/renesas-i3c.c b/drivers/i3c/master/renesas-i3c.c
> new file mode 100644
> index 000000000000..2625462144c4
> --- /dev/null
> +++ b/drivers/i3c/master/renesas-i3c.c
> @@ -0,0 +1,1433 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Renesas I3C Controller driver
> + * Copyright (C) 2023-25 Renesas Electronics Corp.
> + *
> + * TODO: IBI support, HotJoin support, Target support
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/clk.h>
> +#include <linux/completion.h>
> +#include <linux/err.h>
> +#include <linux/errno.h>
> +#include <linux/i2c.h>
> +#include <linux/i3c/master.h>
> +#include <linux/interrupt.h>
> +#include <linux/ioport.h>
> +#include <linux/iopoll.h>
> +#include <linux/list.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/reset.h>
> +#include <linux/slab.h>
> +#include "../internals.h"
> +
> +#define PRTS 0x00
> +#define PRTS_PRTMD BIT(0)
> +
> +#define BCTL 0x14
> +#define BCTL_INCBA BIT(0)
> +#define BCTL_HJACKCTL BIT(8)
> +#define BCTL_ABT BIT(29)
> +#define BCTL_BUSE BIT(31)
> +
> +#define MSDVAD 0x18
> +#define MSDVAD_MDYAD(x) FIELD_PREP(GENMASK(21, 16), x)
> +#define MSDVAD_MDYADV BIT(31)
> +
> +#define RSTCTL 0x20
> +#define RSTCTL_RI3CRST BIT(0)
> +#define RSTCTL_INTLRST BIT(16)
> +
> +#define INST 0x30
> +
> +#define IBINCTL 0x58
> +#define IBINCTL_NRHJCTL BIT(0)
> +#define IBINCTL_NRMRCTL BIT(1)
> +#define IBINCTL_NRSIRCTL BIT(3)
> +
> +#define SVCTL 0x64
> +
> +#define REFCKCTL 0x70
> +#define REFCKCTL_IREFCKS(x) FIELD_PREP(GENMASK(2, 0), x)
> +
> +#define STDBR 0x74
> +#define STDBR_SBRLO(cond, x) FIELD_PREP(GENMASK(7, 0), (x) >> (cond))
> +#define STDBR_SBRHO(cond, x) FIELD_PREP(GENMASK(15, 8), (x) >> (cond))
I think pass down od_low_ticks instead of cond will be easy to understand.
STDBR_SBRLO(l, x) FIELD_PREP(GENMASK(7, 0), (x) >> ((l) > 0xFF > 1: 0)
But still strange, l > 0xFF, you just shift right just 1 bits.
what's happen if l is 0x3ff.
> +#define STDBR_SBRLP(x) FIELD_PREP(GENMASK(21, 16), x)
> +#define STDBR_SBRHP(x) FIELD_PREP(GENMASK(29, 24), x)
> +#define STDBR_DSBRPO BIT(31)
> +
> +#define EXTBR 0x78
> +#define EXTBR_EBRLO(x) FIELD_PREP(GENMASK(7, 0), x)
> +#define EXTBR_EBRHO(x) FIELD_PREP(GENMASK(15, 8), x)
> +#define EXTBR_EBRLP(x) FIELD_PREP(GENMASK(21, 16), x)
> +#define EXTBR_EBRHP(x) FIELD_PREP(GENMASK(29, 24), x)
did this pass check_patch.sh? I remember need (x)
maybe run check_patch.sh --strict
> +
> +#define BFRECDT 0x7c
> +#define BFRECDT_FRECYC(x) FIELD_PREP(GENMASK(8, 0), x)
> +
> +#define BAVLCDT 0x80
> +#define BAVLCDT_AVLCYC(x) FIELD_PREP(GENMASK(8, 0), x)
> +
> +#define BIDLCDT 0x84
> +#define BIDLCDT_IDLCYC(x) FIELD_PREP(GENMASK(17, 0), x)
> +
> +#define ACKCTL 0xa0
> +#define ACKCTL_ACKT BIT(1)
> +#define ACKCTL_ACKTWP BIT(2)
> +
> +#define SCSTRCTL 0xa4
> +#define SCSTRCTL_ACKTWE BIT(0)
> +#define SCSTRCTL_RWE BIT(1)
> +
> +#define SCSTLCTL 0xb0
> +
> +#define CNDCTL 0x140
> +#define CNDCTL_STCND BIT(0)
> +#define CNDCTL_SRCND BIT(1)
> +#define CNDCTL_SPCND BIT(2)
> +
> +#define NCMDQP 0x150 /* Normal Command Queue */
> +#define NCMDQP_CMD_ATTR(x) FIELD_PREP(GENMASK(2, 0), x)
> +#define NCMDQP_IMMED_XFER 0x01
> +#define NCMDQP_ADDR_ASSGN 0x02
> +#define NCMDQP_TID(x) FIELD_PREP(GENMASK(6, 3), x)
> +#define NCMDQP_CMD(x) FIELD_PREP(GENMASK(14, 7), x)
> +#define NCMDQP_CP BIT(15)
> +#define NCMDQP_DEV_INDEX(x) FIELD_PREP(GENMASK(20, 16), x)
> +#define NCMDQP_BYTE_CNT(x) FIELD_PREP(GENMASK(25, 23), x)
> +#define NCMDQP_DEV_COUNT(x) FIELD_PREP(GENMASK(29, 26), x)
> +#define NCMDQP_MODE(x) FIELD_PREP(GENMASK(28, 26), x)
> +#define NCMDQP_RNW(x) FIELD_PREP(GENMASK(29, 29), x)
> +#define NCMDQP_ROC BIT(30)
> +#define NCMDQP_TOC BIT(31)
> +#define NCMDQP_DATA_LENGTH(x) FIELD_PREP(GENMASK(31, 16), x)
> +
> +#define NRSPQP 0x154 /* Normal Respone Queue */
> +#define NRSPQP_NO_ERROR 0
> +#define NRSPQP_ERROR_CRC 1
> +#define NRSPQP_ERROR_PARITY 2
> +#define NRSPQP_ERROR_FRAME 3
> +#define NRSPQP_ERROR_IBA_NACK 4
> +#define NRSPQP_ERROR_ADDRESS_NACK 5
> +#define NRSPQP_ERROR_OVER_UNDER_FLOW 6
> +#define NRSPQP_ERROR_TRANSF_ABORT 8
> +#define NRSPQP_ERROR_I2C_W_NACK_ERR 9
> +#define NRSPQP_ERROR_UNSUPPORTED 10
> +#define NRSPQP_DATA_LEN(x) FIELD_GET(GENMASK(15, 0), x)
> +#define NRSPQP_ERR_STATUS(x) FIELD_GET(GENMASK(31, 28), x)
> +
> +#define NTDTBP0 0x158 /* Normal Transfer Data Buffer */
> +#define NTDTBP0_DEPTH 16
> +
> +#define NQTHCTL 0x190
> +#define NQTHCTL_CMDQTH(x) FIELD_PREP(GENMASK(1, 0), x)
> +#define NQTHCTL_IBIDSSZ(x) FIELD_PREP(GENMASK(23, 16), x)
> +
> +#define NTBTHCTL0 0x194
> +
> +#define NRQTHCTL 0x1c0
> +
> +#define BST 0x1d0
> +#define BST_STCNDDF BIT(0)
> +#define BST_SPCNDDF BIT(1)
> +#define BST_NACKDF BIT(4)
> +#define BST_TENDF BIT(8)
> +
> +#define BSTE 0x1d4
> +#define BSTE_STCNDDE BIT(0)
> +#define BSTE_SPCNDDE BIT(1)
> +#define BSTE_NACKDE BIT(4)
> +#define BSTE_TENDE BIT(8)
> +#define BSTE_ALE BIT(16)
> +#define BSTE_TODE BIT(20)
> +#define BSTE_WUCNDDE BIT(24)
> +#define BSTE_ALL_FLAG (BSTE_STCNDDE | BSTE_SPCNDDE |\
> + BSTE_NACKDE | BSTE_TENDE |\
> + BSTE_ALE | BSTE_TODE | BSTE_WUCNDDE)
> +
> +#define BIE 0x1d8
> +#define BIE_STCNDDIE BIT(0)
> +#define BIE_SPCNDDIE BIT(1)
> +#define BIE_NACKDIE BIT(4)
> +#define BIE_TENDIE BIT(8)
> +
> +#define NTST 0x1e0
> +#define NTST_TDBEF0 BIT(0)
> +#define NTST_RDBFF0 BIT(1)
> +#define NTST_CMDQEF BIT(3)
> +#define NTST_RSPQFF BIT(4)
> +#define NTST_TABTF BIT(5)
> +#define NTST_TEF BIT(9)
> +
> +#define NTSTE 0x1e4
> +#define NTSTE_TDBEE0 BIT(0)
> +#define NTSTE_RDBFE0 BIT(1)
> +#define NTSTE_IBIQEFE BIT(2)
> +#define NTSTE_CMDQEE BIT(3)
> +#define NTSTE_RSPQFE BIT(4)
> +#define NTSTE_TABTE BIT(5)
> +#define NTSTE_TEE BIT(9)
> +#define NTSTE_RSQFE BIT(20)
> +#define NTSTE_ALL_FLAG (NTSTE_TDBEE0 | NTSTE_RDBFE0 |\
> + NTSTE_IBIQEFE | NTSTE_CMDQEE |\
> + NTSTE_RSPQFE | NTSTE_TABTE |\
> + NTSTE_TEE | NTSTE_RSQFE)
> +
> +#define NTIE 0x1e8
> +#define NTIE_TDBEIE0 BIT(0)
> +#define NTIE_RDBFIE0 BIT(1)
> +#define NTIE_IBIQEFIE BIT(2)
> +#define NTIE_RSPQFIE BIT(4)
> +#define NTIE_RSQFIE BIT(20)
> +
> +#define BCST 0x210
> +#define BCST_BFREF BIT(0)
> +
> +#define DATBAS(x) (0x224 + 0x8 * (x))
> +#define DATBAS_DVSTAD(x) FIELD_PREP(GENMASK(6, 0), x)
> +#define DATBAS_DVDYAD(x) FIELD_PREP(GENMASK(23, 16), x)
> +
> +#define NDBSTLV0 0x398
> +#define NDBSTLV0_RDBLV(x) (((x) >> 8) & 0xff)
> +
> +#define RENESAS_I3C_MAX_DEVS 8
> +#define I2C_INIT_MSG -1
> +
> +/* Bus condition timing */
> +#define I3C_BUS_THIGH_MIXED_NS 40 /* 40ns */
> +#define I3C_BUS_FREE_TIME_NS 1300 /* 1.3us for Mixed Bus with I2C FM Device*/
> +#define I3C_BUS_AVAL_TIME_NS 1000 /* 1us */
> +#define I3C_BUS_IDLE_TIME_NS 200000 /* 200us */
> +
> +#define XFER_TIMEOUT (msecs_to_jiffies(1000))
> +
> +enum i3c_internal_state {
> + I3C_INTERNAL_STATE_DISABLED,
> + I3C_INTERNAL_STATE_CONTROLLER_IDLE,
> + I3C_INTERNAL_STATE_CONTROLLER_ENTDAA,
> + I3C_INTERNAL_STATE_CONTROLLER_SETDASA,
> + I3C_INTERNAL_STATE_CONTROLLER_WRITE,
> + I3C_INTERNAL_STATE_CONTROLLER_READ,
> + I3C_INTERNAL_STATE_CONTROLLER_COMMAND_WRITE,
> + I3C_INTERNAL_STATE_CONTROLLER_COMMAND_READ,
> +};
> +
> +enum i3c_event {
> + I3C_COMMAND_ADDRESS_ASSIGNMENT,
> + I3C_WRITE,
> + I3C_READ,
> + I3C_COMMAND_WRITE,
> + I3C_COMMAND_READ,
> +};
> +
> +struct renesas_i3c_cmd {
> + u32 cmd0;
> + u32 len;
> + const void *tx_buf;
> + u32 tx_count;
> + void *rx_buf;
> + u32 rx_count;
> + u32 err;
> + u8 rnw;
> + /* i2c xfer */
> + int i2c_bytes_left;
> + int i2c_is_last;
> + u8 *i2c_buf;
> + const struct i2c_msg *msg;
> +};
> +
> +struct renesas_i3c_xfer {
> + struct list_head node;
> + struct completion comp;
> + int ret;
> + bool is_i2c_xfer;
> + unsigned int ncmds;
> + struct renesas_i3c_cmd cmds[] __counted_by(ncmds);
> +};
> +
> +struct renesas_i3c_xferqueue {
> + struct list_head list;
> + struct renesas_i3c_xfer *cur;
> + /* Lock for accessing the xfer queue */
> + spinlock_t lock;
> +};
> +
> +struct renesas_i3c {
> + struct i3c_master_controller base;
> + enum i3c_internal_state internal_state;
> + u16 maxdevs;
> + u32 free_pos;
> + u32 i2c_STDBR;
> + u32 i3c_STDBR;
> + u8 addrs[RENESAS_I3C_MAX_DEVS];
> + struct renesas_i3c_xferqueue xferqueue;
> + void __iomem *regs;
> + struct clk *tclk;
> +};
> +
> +struct renesas_i3c_i2c_dev_data {
> + u8 index;
> +};
> +
> +struct renesas_i3c_irq_desc {
> + char *name;
> + irq_handler_t isr;
> + char *desc;
> +};
> +
> +struct renesas_i3c_config {
> + unsigned int has_pclkrw:1;
> +};
> +
> +static inline void i3c_reg_update(void __iomem *reg, u32 mask, u32 val)
> +{
> + u32 data = readl(reg);
> +
> + data &= ~mask;
> + data |= (val & mask);
> + writel(data, reg);
> +}
> +
> +static inline u32 i3c_reg_read(void __iomem *base, u32 reg)
> +{
> + return readl(base + reg);
> +}
> +
> +static inline void i3c_reg_write(void __iomem *base, u32 reg, u32 val)
> +{
> + writel(val, base + reg);
> +}
> +
> +static void i3c_reg_set_bit(void __iomem *base, u32 reg, u32 val)
> +{
> + i3c_reg_update(base + reg, val, val);
> +}
> +
> +static void i3c_reg_clear_bit(void __iomem *base, u32 reg, u32 val)
> +{
> + i3c_reg_update(base + reg, val, 0);
> +}
> +
> +static void i3c_reg_update_bit(void __iomem *base, u32 reg,
> + u32 mask, u32 val)
> +{
> + i3c_reg_update(base + reg, mask, val);
> +}
It is similor to regmap. If you use mmios' regmap, needn't above help
functions.
> +
> +static inline struct renesas_i3c *
> +to_renesas_i3c(struct i3c_master_controller *master)
> +{
> + return container_of(master, struct renesas_i3c, base);
> +}
> +
> +static inline u32 datbas_dvdyad_with_parity(u8 addr)
> +{
> + return DATBAS_DVDYAD(addr | (parity8(addr) ? 0 : BIT(7)));
> +}
> +
> +static int renesas_i3c_get_free_pos(struct renesas_i3c *i3c)
> +{
> + if (!(i3c->free_pos & GENMASK(i3c->maxdevs - 1, 0)))
> + return -ENOSPC;
> +
> + return ffs(i3c->free_pos) - 1;
> +}
> +
> +static int renesas_i3c_get_addr_pos(struct renesas_i3c *i3c, u8 addr)
> +{
> + int pos;
> +
> + for (pos = 0; pos < i3c->maxdevs; pos++) {
> + if (addr == i3c->addrs[pos])
> + return pos;
> + }
> +
> + return -EINVAL;
> +}
> +
> +static struct renesas_i3c_xfer *
> +renesas_i3c_alloc_xfer(struct renesas_i3c *i3c, unsigned int ncmds)
> +{
> + struct renesas_i3c_xfer *xfer;
> +
> + xfer = kzalloc(struct_size(xfer, cmds, ncmds), GFP_KERNEL);
> + if (!xfer)
> + return NULL;
> +
> + INIT_LIST_HEAD(&xfer->node);
> + xfer->ncmds = ncmds;
> + xfer->ret = -ETIMEDOUT;
> +
> + return xfer;
> +}
> +
> +static void renesas_i3c_start_xfer_locked(struct renesas_i3c *i3c)
> +{
> + struct renesas_i3c_xfer *xfer = i3c->xferqueue.cur;
> + struct renesas_i3c_cmd *cmd;
> + u32 cmd1;
> +
> + if (!xfer)
> + return;
> +
> + cmd = xfer->cmds;
> +
> + switch (i3c->internal_state) {
> + case I3C_INTERNAL_STATE_CONTROLLER_ENTDAA:
> + case I3C_INTERNAL_STATE_CONTROLLER_SETDASA:
> + i3c_reg_set_bit(i3c->regs, NTIE, NTIE_RSPQFIE);
> + i3c_reg_write(i3c->regs, NCMDQP, cmd->cmd0);
> + i3c_reg_write(i3c->regs, NCMDQP, 0);
> + break;
> + case I3C_INTERNAL_STATE_CONTROLLER_WRITE:
> + case I3C_INTERNAL_STATE_CONTROLLER_COMMAND_WRITE:
> + i3c_reg_set_bit(i3c->regs, NTIE, NTIE_RSPQFIE);
> + if (cmd->len <= 4) {
> + cmd->cmd0 |= NCMDQP_CMD_ATTR(NCMDQP_IMMED_XFER);
> + cmd->cmd0 |= NCMDQP_BYTE_CNT(cmd->len);
> + cmd->tx_count = cmd->len;
> + cmd1 = cmd->len == 0 ? 0 : *(u32 *)cmd->tx_buf;
> + } else {
> + cmd1 = NCMDQP_DATA_LENGTH(cmd->len);
> + }
> + i3c_reg_write(i3c->regs, NCMDQP, cmd->cmd0);
> + i3c_reg_write(i3c->regs, NCMDQP, cmd1);
> + break;
> + case I3C_INTERNAL_STATE_CONTROLLER_READ:
> + case I3C_INTERNAL_STATE_CONTROLLER_COMMAND_READ:
> + i3c_reg_set_bit(i3c->regs, NTIE, NTIE_RDBFIE0);
> + cmd1 = NCMDQP_DATA_LENGTH(cmd->len);
> + i3c_reg_write(i3c->regs, NCMDQP, cmd->cmd0);
> + i3c_reg_write(i3c->regs, NCMDQP, cmd1);
> + break;
> + default:
> + break;
> + }
> +
> + /* Clear the command queue empty flag */
> + i3c_reg_clear_bit(i3c->regs, NTST, NTST_CMDQEF);
> +}
> +
> +static void renesas_i3c_dequeue_xfer_locked(struct renesas_i3c *i3c,
> + struct renesas_i3c_xfer *xfer)
> +{
> + if (i3c->xferqueue.cur == xfer)
> + i3c->xferqueue.cur = NULL;
> + else
> + list_del_init(&xfer->node);
> +}
> +
> +static void renesas_i3c_dequeue_xfer(struct renesas_i3c *i3c, struct renesas_i3c_xfer *xfer)
> +{
> + scoped_guard(spinlock_irqsave, &i3c->xferqueue.lock)
> + renesas_i3c_dequeue_xfer_locked(i3c, xfer);
> +}
> +
> +static void renesas_i3c_enqueue_xfer(struct renesas_i3c *i3c, struct renesas_i3c_xfer *xfer)
> +{
> + reinit_completion(&xfer->comp);
> + scoped_guard(spinlock_irqsave, &i3c->xferqueue.lock) {
> + if (i3c->xferqueue.cur) {
> + list_add_tail(&xfer->node, &i3c->xferqueue.list);
> + } else {
> + i3c->xferqueue.cur = xfer;
> + if (!xfer->is_i2c_xfer)
> + renesas_i3c_start_xfer_locked(i3c);
> + }
> + }
> +}
> +
> +static void renesas_i3c_wait_xfer(struct renesas_i3c *i3c, struct renesas_i3c_xfer *xfer)
> +{
> + unsigned long time_left;
> +
> + renesas_i3c_enqueue_xfer(i3c, xfer);
> +
> + time_left = wait_for_completion_timeout(&xfer->comp, XFER_TIMEOUT);
> + if (!time_left)
> + renesas_i3c_dequeue_xfer(i3c, xfer);
> +}
> +
> +static void renesas_i3c_set_prts(struct renesas_i3c *i3c, u32 val)
> +{
> + /* Required sequence according to tnrza0140ae */
> + i3c_reg_set_bit(i3c->regs, RSTCTL, RSTCTL_INTLRST);
> + i3c_reg_write(i3c->regs, PRTS, val);
> + i3c_reg_clear_bit(i3c->regs, RSTCTL, RSTCTL_INTLRST);
> +}
> +
> +static void renesas_i3c_bus_enable(struct i3c_master_controller *m, bool i3c_mode)
> +{
> + struct renesas_i3c *i3c = to_renesas_i3c(m);
> +
> + /* Setup either I3C or I2C protocol */
> + if (i3c_mode) {
> + renesas_i3c_set_prts(i3c, 0);
> + /* Revisit: INCBA handling, especially after I2C transfers */
> + i3c_reg_set_bit(i3c->regs, BCTL, BCTL_HJACKCTL | BCTL_INCBA);
> + i3c_reg_set_bit(i3c->regs, MSDVAD, MSDVAD_MDYADV);
> + i3c_reg_write(i3c->regs, STDBR, i3c->i3c_STDBR);
> + } else {
> + renesas_i3c_set_prts(i3c, PRTS_PRTMD);
> + i3c_reg_write(i3c->regs, STDBR, i3c->i2c_STDBR);
> + }
> +
> + /* Enable I3C bus */
> + i3c_reg_set_bit(i3c->regs, BCTL, BCTL_BUSE);
> +}
> +
> +static int renesas_i3c_reset(struct renesas_i3c *i3c)
> +{
> + u32 val;
> +
> + i3c_reg_write(i3c->regs, BCTL, 0);
> + i3c_reg_set_bit(i3c->regs, RSTCTL, RSTCTL_RI3CRST);
> +
> + /* Wait for reset completion */
> + return readl_relaxed_poll_timeout(i3c->regs + RSTCTL, val,
> + !(val & RSTCTL_RI3CRST), 0, 1000);
> +}
> +
> +static int renesas_i3c_bus_init(struct i3c_master_controller *m)
> +{
> + struct renesas_i3c *i3c = to_renesas_i3c(m);
> + struct i3c_bus *bus = i3c_master_get_bus(m);
> + struct i3c_device_info info = {};
> + struct i2c_timings t;
> + unsigned long rate;
> + u32 double_SBR, val;
> + int cks, pp_high_ticks, pp_low_ticks, i3c_total_ticks;
> + int od_high_ticks, od_low_ticks, i2c_total_ticks;
> + int ret;
> +
> + rate = clk_get_rate(i3c->tclk);
> + if (!rate)
> + return -EINVAL;
> +
> + ret = renesas_i3c_reset(i3c);
> + if (ret)
> + return ret;
> +
> + i2c_total_ticks = DIV_ROUND_UP(rate, bus->scl_rate.i2c);
> + i3c_total_ticks = DIV_ROUND_UP(rate, bus->scl_rate.i3c);
> +
> + i2c_parse_fw_timings(&m->dev, &t, true);
> +
> + for (cks = 0; cks < 7; cks++) {
> + /* SCL low-period calculation in Open-drain mode */
> + od_low_ticks = ((i2c_total_ticks * 6) / 10);
> +
> + /* SCL clock calculation in Push-Pull mode */
> + if (bus->mode == I3C_BUS_MODE_PURE)
> + pp_high_ticks = ((i3c_total_ticks * 5) / 10);
> + else
> + pp_high_ticks = DIV_ROUND_UP(I3C_BUS_THIGH_MIXED_NS,
> + 1000000000 / rate);
> + pp_low_ticks = i3c_total_ticks - pp_high_ticks;
> +
> + if ((od_low_ticks / 2) <= 0xFF && pp_low_ticks < 0x3F)
> + break;
> +
> + i2c_total_ticks /= 2;
> + i3c_total_ticks /= 2;
> + rate /= 2;
> + }
> +
> + /* SCL clock period calculation in Open-drain mode */
> + if ((od_low_ticks / 2) > 0xFF || pp_low_ticks > 0x3F) {
> + dev_err(&m->dev, "invalid speed (i2c-scl = %lu Hz, i3c-scl = %lu Hz). Too slow.\n",
> + (unsigned long)bus->scl_rate.i2c, (unsigned long)bus->scl_rate.i3c);
> + ret = -EINVAL;
> + return ret;
> + }
> +
> + /* SCL high-period calculation in Open-drain mode */
> + od_high_ticks = i2c_total_ticks - od_low_ticks;
> +
> + /* Standard Bit Rate setting */
> + double_SBR = od_low_ticks > 0xFF ? 1 : 0;
> + i3c->i3c_STDBR = (double_SBR ? STDBR_DSBRPO : 0) |
> + STDBR_SBRLO(double_SBR, od_low_ticks) |
> + STDBR_SBRHO(double_SBR, od_high_ticks) |
> + STDBR_SBRLP(pp_low_ticks) |
> + STDBR_SBRHP(pp_high_ticks);
> +
> + od_low_ticks -= t.scl_fall_ns / (1000000000 / rate) + 1;
> + od_high_ticks -= t.scl_rise_ns / (1000000000 / rate) + 1;
> + i3c->i2c_STDBR = (double_SBR ? STDBR_DSBRPO : 0) |
> + STDBR_SBRLO(double_SBR, od_low_ticks) |
> + STDBR_SBRHO(double_SBR, od_high_ticks) |
> + STDBR_SBRLP(pp_low_ticks) |
> + STDBR_SBRHP(pp_high_ticks);
> + i3c_reg_write(i3c->regs, STDBR, i3c->i3c_STDBR);
> +
> + /* Extended Bit Rate setting */
> + i3c_reg_write(i3c->regs, EXTBR, EXTBR_EBRLO(od_low_ticks) |
> + EXTBR_EBRHO(od_high_ticks) |
> + EXTBR_EBRLP(pp_low_ticks) |
> + EXTBR_EBRHP(pp_high_ticks));
> +
> + i3c_reg_write(i3c->regs, REFCKCTL, REFCKCTL_IREFCKS(cks));
> +
> + /* Disable Slave Mode */
> + i3c_reg_write(i3c->regs, SVCTL, 0);
> +
> + /* Initialize Queue/Buffer threshold */
> + i3c_reg_write(i3c->regs, NQTHCTL, NQTHCTL_IBIDSSZ(6) |
> + NQTHCTL_CMDQTH(1));
> +
> + /* The only supported configuration is two entries*/
> + i3c_reg_write(i3c->regs, NTBTHCTL0, 0);
> + /* Interrupt when there is one entry in the queue */
> + i3c_reg_write(i3c->regs, NRQTHCTL, 0);
> +
> + /* Enable all Bus/Transfer Status Flags */
> + i3c_reg_write(i3c->regs, BSTE, BSTE_ALL_FLAG);
> + i3c_reg_write(i3c->regs, NTSTE, NTSTE_ALL_FLAG);
> +
> + /* Interrupt enable settings */
> + i3c_reg_write(i3c->regs, BIE, BIE_NACKDIE | BIE_TENDIE);
> + i3c_reg_write(i3c->regs, NTIE, 0);
> +
> + /* Clear Status register */
> + i3c_reg_write(i3c->regs, NTST, 0);
> + i3c_reg_write(i3c->regs, INST, 0);
> + i3c_reg_write(i3c->regs, BST, 0);
> +
> + /* Hot-Join Acknowlege setting. */
> + i3c_reg_update_bit(i3c->regs, BCTL, BCTL_HJACKCTL, BCTL_HJACKCTL);
> +
> + i3c_reg_write(i3c->regs, IBINCTL, IBINCTL_NRHJCTL | IBINCTL_NRMRCTL |
> + IBINCTL_NRSIRCTL);
> +
> + i3c_reg_write(i3c->regs, SCSTLCTL, 0);
> + i3c_reg_set_bit(i3c->regs, SCSTRCTL, SCSTRCTL_ACKTWE);
> +
> + /* Bus condition timing */
> + val = DIV_ROUND_UP(I3C_BUS_FREE_TIME_NS, 1000000000 / rate);
> + i3c_reg_write(i3c->regs, BFRECDT, BFRECDT_FRECYC(val));
> +
> + val = DIV_ROUND_UP(I3C_BUS_AVAL_TIME_NS, 1000000000 / rate);
> + i3c_reg_write(i3c->regs, BAVLCDT, BAVLCDT_AVLCYC(val));
> +
> + val = DIV_ROUND_UP(I3C_BUS_IDLE_TIME_NS, 1000000000 / rate);
> + i3c_reg_write(i3c->regs, BIDLCDT, BIDLCDT_IDLCYC(val));
> +
> + ret = i3c_master_get_free_addr(m, 0);
> + if (ret < 0)
> + return ret;
> +
> + i3c_reg_write(i3c->regs, MSDVAD, MSDVAD_MDYAD(ret) | MSDVAD_MDYADV);
> +
> + memset(&info, 0, sizeof(info));
> + info.dyn_addr = ret;
> + return i3c_master_set_info(&i3c->base, &info);
> +}
> +
> +static void renesas_i3c_bus_cleanup(struct i3c_master_controller *m)
> +{
> + struct renesas_i3c *i3c = to_renesas_i3c(m);
> + u32 val;
> +
> + i3c_reg_write(i3c->regs, BCTL, 0);
> + i3c_reg_update_bit(i3c->regs, RSTCTL, RSTCTL_RI3CRST, RSTCTL_RI3CRST);
> + /* Wait for reset completion */
> + readl_relaxed_poll_timeout(i3c->regs + RSTCTL, val,
> + !(val & RSTCTL_RI3CRST), 0, 1000);
> +}
> +
> +static int renesas_i3c_daa(struct i3c_master_controller *m)
> +{
> + struct renesas_i3c *i3c = to_renesas_i3c(m);
> + struct renesas_i3c_xfer *xfer;
> + struct renesas_i3c_cmd *cmd;
> + u32 olddevs, newdevs;
> + u8 last_addr = 0, pos;
> + int ret;
> +
> + /* Enable I3C bus. */
> + renesas_i3c_bus_enable(m, true);
> +
> + olddevs = ~(i3c->free_pos);
> + i3c->internal_state = I3C_INTERNAL_STATE_CONTROLLER_ENTDAA;
> +
> + /* Setting DATBASn registers for target devices. */
> + for (pos = 0; pos < i3c->maxdevs; pos++) {
> + if (olddevs & BIT(pos))
> + continue;
> +
> + ret = i3c_master_get_free_addr(m, last_addr + 1);
> + if (ret < 0)
> + return -ENOSPC;
> +
> + i3c->addrs[pos] = ret;
> + last_addr = ret;
> +
> + i3c_reg_write(i3c->regs, DATBAS(pos), datbas_dvdyad_with_parity(ret));
> + }
> +
> + xfer = renesas_i3c_alloc_xfer(i3c, 1);
> + if (!xfer)
> + return -ENOMEM;
> +
> + init_completion(&xfer->comp);
> + cmd = xfer->cmds;
> + cmd->rx_count = 0;
> +
> + ret = renesas_i3c_get_free_pos(i3c);
> + if (ret < 0)
> + goto out;
> +
> + /*
> + * Setup the command descriptor to start the ENTDAA command
> + * and starting at the selected device index.
> + */
> + cmd->cmd0 = NCMDQP_CMD_ATTR(NCMDQP_ADDR_ASSGN) | NCMDQP_ROC |
> + NCMDQP_TID(I3C_COMMAND_ADDRESS_ASSIGNMENT) |
> + NCMDQP_CMD(I3C_CCC_ENTDAA) | NCMDQP_DEV_INDEX(ret) |
> + NCMDQP_DEV_COUNT(i3c->maxdevs - ret) | NCMDQP_TOC;
> +
> + renesas_i3c_wait_xfer(i3c, xfer);
> +
> + newdevs = GENMASK(i3c->maxdevs - cmd->rx_count - 1, 0);
> + newdevs &= ~olddevs;
> +
> + for (pos = 0; pos < i3c->maxdevs; pos++) {
> + if (newdevs & BIT(pos))
> + i3c_master_add_i3c_dev_locked(m, i3c->addrs[pos]);
> + }
> +
> +out:
> + kfree(xfer);
> + return ret < 0 ? ret : 0;
> +}
> +
> +static bool renesas_i3c_supports_ccc_cmd(struct i3c_master_controller *m,
> + const struct i3c_ccc_cmd *cmd)
> +{
> + if (cmd->ndests > 1)
> + return false;
> +
> + switch (cmd->id) {
> + case I3C_CCC_ENEC(true):
> + case I3C_CCC_ENEC(false):
> + case I3C_CCC_DISEC(true):
> + case I3C_CCC_DISEC(false):
> + case I3C_CCC_ENTAS(0, true):
> + case I3C_CCC_ENTAS(1, true):
> + case I3C_CCC_ENTAS(2, true):
> + case I3C_CCC_ENTAS(3, true):
> + case I3C_CCC_ENTAS(0, false):
> + case I3C_CCC_ENTAS(1, false):
> + case I3C_CCC_ENTAS(2, false):
> + case I3C_CCC_ENTAS(3, false):
> + case I3C_CCC_RSTDAA(true):
> + case I3C_CCC_RSTDAA(false):
> + case I3C_CCC_ENTDAA:
> + case I3C_CCC_DEFSLVS:
> + case I3C_CCC_SETMWL(true):
> + case I3C_CCC_SETMWL(false):
> + case I3C_CCC_SETMRL(true):
> + case I3C_CCC_SETMRL(false):
> + case I3C_CCC_ENTTM:
> + case I3C_CCC_SETDASA:
> + case I3C_CCC_SETNEWDA:
> + case I3C_CCC_GETMWL:
> + case I3C_CCC_GETMRL:
> + case I3C_CCC_GETPID:
> + case I3C_CCC_GETBCR:
> + case I3C_CCC_GETDCR:
> + case I3C_CCC_GETSTATUS:
> + case I3C_CCC_GETACCMST:
> + case I3C_CCC_GETMXDS:
> + return true;
> + default:
> + return false;
> + }
> +}
> +
> +static int renesas_i3c_send_ccc_cmd(struct i3c_master_controller *m,
> + struct i3c_ccc_cmd *ccc)
> +{
> + struct renesas_i3c *i3c = to_renesas_i3c(m);
> + struct renesas_i3c_xfer *xfer;
> + struct renesas_i3c_cmd *cmd;
> + int ret, pos = 0;
> +
> + if (ccc->id & I3C_CCC_DIRECT) {
> + pos = renesas_i3c_get_addr_pos(i3c, ccc->dests[0].addr);
> + if (pos < 0)
> + return pos;
> + }
> +
> + xfer = renesas_i3c_alloc_xfer(i3c, 1);
> + if (!xfer)
> + return -ENOMEM;
> +
> + renesas_i3c_bus_enable(m, true);
> +
> + init_completion(&xfer->comp);
> + cmd = xfer->cmds;
> + cmd->rnw = ccc->rnw;
> + cmd->cmd0 = 0;
> +
> + /* Calculate the command descriptor. */
> + switch (ccc->id) {
> + case I3C_CCC_SETDASA:
> + i3c_reg_write(i3c->regs, DATBAS(pos),
> + DATBAS_DVSTAD(ccc->dests[0].addr) |
> + DATBAS_DVDYAD(*(u8 *)ccc->dests[0].payload.data >> 1));
> + cmd->cmd0 = NCMDQP_CMD_ATTR(NCMDQP_ADDR_ASSGN) | NCMDQP_ROC |
> + NCMDQP_TID(I3C_COMMAND_ADDRESS_ASSIGNMENT) |
> + NCMDQP_CMD(I3C_CCC_SETDASA) | NCMDQP_DEV_INDEX(pos) |
> + NCMDQP_DEV_COUNT(0) | NCMDQP_TOC;
> + i3c->internal_state = I3C_INTERNAL_STATE_CONTROLLER_SETDASA;
> + break;
> + default:
> + /* Calculate the command descriptor. */
> + cmd->cmd0 = NCMDQP_TID(I3C_COMMAND_WRITE) | NCMDQP_MODE(0) |
> + NCMDQP_RNW(ccc->rnw) | NCMDQP_CMD(ccc->id) |
> + NCMDQP_ROC | NCMDQP_TOC | NCMDQP_CP |
> + NCMDQP_DEV_INDEX(pos);
> +
> + if (ccc->rnw) {
> + cmd->rx_buf = ccc->dests[0].payload.data;
> + cmd->len = ccc->dests[0].payload.len;
> + cmd->rx_count = 0;
> + i3c->internal_state = I3C_INTERNAL_STATE_CONTROLLER_COMMAND_READ;
> + } else {
> + cmd->tx_buf = ccc->dests[0].payload.data;
> + cmd->len = ccc->dests[0].payload.len;
> + cmd->tx_count = 0;
> + i3c->internal_state = I3C_INTERNAL_STATE_CONTROLLER_COMMAND_WRITE;
> + }
> + }
> +
> + renesas_i3c_wait_xfer(i3c, xfer);
> +
> + ret = xfer->ret;
> + if (ret)
> + ccc->err = I3C_ERROR_M2;
> +
> + kfree(xfer);
> +
> + return ret;
> +}
> +
> +static int renesas_i3c_priv_xfers(struct i3c_dev_desc *dev, struct i3c_priv_xfer *i3c_xfers,
> + int i3c_nxfers)
> +{
> + struct i3c_master_controller *m = i3c_dev_get_master(dev);
> + struct renesas_i3c *i3c = to_renesas_i3c(m);
> + struct renesas_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
> + struct renesas_i3c_xfer *xfer;
> + int i;
> +
> + /* Enable I3C bus. */
> + renesas_i3c_bus_enable(m, true);
> +
> + xfer = renesas_i3c_alloc_xfer(i3c, 1);
> + if (!xfer)
> + return -ENOMEM;
> +
> + init_completion(&xfer->comp);
> +
> + for (i = 0; i < i3c_nxfers; i++) {
> + struct renesas_i3c_cmd *cmd = xfer->cmds;
> +
> + /* Calculate the Transfer Command Descriptor */
> + cmd->rnw = i3c_xfers[i].rnw;
> + cmd->cmd0 = NCMDQP_DEV_INDEX(data->index) | NCMDQP_MODE(0) |
> + NCMDQP_RNW(cmd->rnw) | NCMDQP_ROC | NCMDQP_TOC;
> +
> + if (i3c_xfers[i].rnw) {
> + cmd->rx_count = 0;
> + cmd->cmd0 |= NCMDQP_TID(I3C_READ);
> + cmd->rx_buf = i3c_xfers[i].data.in;
> + cmd->len = i3c_xfers[i].len;
> + i3c->internal_state = I3C_INTERNAL_STATE_CONTROLLER_READ;
> + } else {
> + cmd->tx_count = 0;
> + cmd->cmd0 |= NCMDQP_TID(I3C_WRITE);
> + cmd->tx_buf = i3c_xfers[i].data.out;
> + cmd->len = i3c_xfers[i].len;
> + i3c->internal_state = I3C_INTERNAL_STATE_CONTROLLER_WRITE;
> + }
> +
> + if (!i3c_xfers[i].rnw && i3c_xfers[i].len > 4) {
> + i3c_writel_fifo(i3c->regs + NTDTBP0, cmd->tx_buf, cmd->len);
> + if (cmd->len > NTDTBP0_DEPTH * sizeof(u32))
> + i3c_reg_set_bit(i3c->regs, NTIE, NTIE_TDBEIE0);
> + }
> +
> + renesas_i3c_wait_xfer(i3c, xfer);
> + }
> +
> + return 0;
> +}
> +
> +static int renesas_i3c_attach_i3c_dev(struct i3c_dev_desc *dev)
> +{
> + struct i3c_master_controller *m = i3c_dev_get_master(dev);
> + struct renesas_i3c *i3c = to_renesas_i3c(m);
> + struct renesas_i3c_i2c_dev_data *data;
> + int pos;
> +
> + pos = renesas_i3c_get_free_pos(i3c);
> + if (pos < 0)
> + return pos;
> +
> + data = kzalloc(sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + data->index = pos;
> + i3c->addrs[pos] = dev->info.dyn_addr ? : dev->info.static_addr;
> + i3c->free_pos &= ~BIT(pos);
> +
> + i3c_reg_write(i3c->regs, DATBAS(pos), DATBAS_DVSTAD(dev->info.static_addr) |
> + datbas_dvdyad_with_parity(i3c->addrs[pos]));
> + i3c_dev_set_master_data(dev, data);
> +
> + return 0;
> +}
> +
> +static int renesas_i3c_reattach_i3c_dev(struct i3c_dev_desc *dev,
> + u8 old_dyn_addr)
> +{
> + struct i3c_master_controller *m = i3c_dev_get_master(dev);
> + struct renesas_i3c *i3c = to_renesas_i3c(m);
> + struct renesas_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
> +
> + i3c->addrs[data->index] = dev->info.dyn_addr ? dev->info.dyn_addr :
> + dev->info.static_addr;
> +
> + return 0;
> +}
> +
> +static void renesas_i3c_detach_i3c_dev(struct i3c_dev_desc *dev)
> +{
> + struct renesas_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
> + struct i3c_master_controller *m = i3c_dev_get_master(dev);
> + struct renesas_i3c *i3c = to_renesas_i3c(m);
> +
> + i3c_dev_set_master_data(dev, NULL);
> + i3c->addrs[data->index] = 0;
> + i3c->free_pos |= BIT(data->index);
> + kfree(data);
> +}
> +
> +static int renesas_i3c_i2c_xfers(struct i2c_dev_desc *dev,
> + struct i2c_msg *i2c_xfers,
> + int i2c_nxfers)
> +{
> + struct i3c_master_controller *m = i2c_dev_get_master(dev);
> + struct renesas_i3c *i3c = to_renesas_i3c(m);
> + struct renesas_i3c_xfer *xfer;
> + struct renesas_i3c_cmd *cmd;
> + u8 start_bit = CNDCTL_STCND;
> + int ret, i;
> +
> + if (!i2c_nxfers)
> + return 0;
> +
> + renesas_i3c_bus_enable(m, false);
> +
> + xfer = renesas_i3c_alloc_xfer(i3c, 1);
> + if (!xfer)
> + return -ENOMEM;
> +
> + init_completion(&xfer->comp);
> + xfer->is_i2c_xfer = true;
> + cmd = xfer->cmds;
> +
> + if (!(i3c_reg_read(i3c->regs, BCST) & BCST_BFREF)) {
> + cmd->err = -EBUSY;
> + goto out;
> + }
> +
> + i3c_reg_write(i3c->regs, BST, 0);
> +
> + renesas_i3c_enqueue_xfer(i3c, xfer);
You can use refer mutex GUARD define to pair renesas_i3c_enqueue_xfer()
and renesas_i3c_dequeue_xfer().
> +
> + for (i = 0; i < i2c_nxfers; i++) {
> + cmd->i2c_bytes_left = I2C_INIT_MSG;
> + cmd->i2c_buf = i2c_xfers[i].buf;
> + cmd->msg = &i2c_xfers[i];
> + cmd->i2c_is_last = (i == i2c_nxfers - 1);
> +
> + i3c_reg_set_bit(i3c->regs, BIE, BIE_NACKDIE);
> + i3c_reg_set_bit(i3c->regs, NTIE, NTIE_TDBEIE0);
> + i3c_reg_set_bit(i3c->regs, BIE, BIE_STCNDDIE);
> +
> + /* Issue Start condition */
> + i3c_reg_set_bit(i3c->regs, CNDCTL, start_bit);
> +
> + i3c_reg_set_bit(i3c->regs, NTSTE, NTSTE_TDBEE0);
> +
> + wait_for_completion_timeout(&xfer->comp, m->i2c.timeout);
> +
> + if (cmd->err)
> + break;
> +
> + start_bit = CNDCTL_SRCND;
> + }
> +out:
> + renesas_i3c_dequeue_xfer(i3c, xfer);
> + ret = cmd->err;
> + kfree(xfer);
struct renesas_i3c_xfer *xfer __free(kfree) = renesas_i3c_alloc_xfer(i3c, 1);
Then whole goto can be elimiated.
> + return ret ?: 0;
> +}
> +
> +static int renesas_i3c_attach_i2c_dev(struct i2c_dev_desc *dev)
> +{
> + struct i3c_master_controller *m = i2c_dev_get_master(dev);
> + struct renesas_i3c *i3c = to_renesas_i3c(m);
> + struct renesas_i3c_i2c_dev_data *data;
> + int pos;
> +
> + pos = renesas_i3c_get_free_pos(i3c);
> + if (pos < 0)
> + return pos;
> +
> + data = kzalloc(sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + data->index = pos;
> + i3c->addrs[pos] = dev->addr;
> + i3c->free_pos &= ~BIT(pos);
> + i2c_dev_set_master_data(dev, data);
> +
> + return 0;
> +}
> +
> +static void renesas_i3c_detach_i2c_dev(struct i2c_dev_desc *dev)
> +{
> + struct renesas_i3c_i2c_dev_data *data = i2c_dev_get_master_data(dev);
> + struct i3c_master_controller *m = i2c_dev_get_master(dev);
> + struct renesas_i3c *i3c = to_renesas_i3c(m);
> +
> + i2c_dev_set_master_data(dev, NULL);
> + i3c->addrs[data->index] = 0;
> + i3c->free_pos |= BIT(data->index);
> + kfree(data);
> +}
> +
> +static irqreturn_t renesas_i3c_tx_isr(int irq, void *data)
> +{
> + struct renesas_i3c *i3c = data;
> + struct renesas_i3c_xfer *xfer;
> + struct renesas_i3c_cmd *cmd;
> + u8 val;
> +
> + scoped_guard(spinlock, &i3c->xferqueue.lock) {
> + xfer = i3c->xferqueue.cur;
> + cmd = xfer->cmds;
> +
> + if (xfer->is_i2c_xfer) {
> + if (!cmd->i2c_bytes_left)
> + return IRQ_NONE;
> +
> + if (cmd->i2c_bytes_left != I2C_INIT_MSG) {
> + val = *cmd->i2c_buf;
> + cmd->i2c_buf++;
> + cmd->i2c_bytes_left--;
> + i3c_reg_write(i3c->regs, NTDTBP0, val);
> + }
> +
> + if (cmd->i2c_bytes_left == 0) {
> + i3c_reg_clear_bit(i3c->regs, NTIE, NTIE_TDBEIE0);
> + i3c_reg_set_bit(i3c->regs, BIE, BIE_TENDIE);
> + }
> +
> + /* Clear the Transmit Buffer Empty status flag. */
> + i3c_reg_clear_bit(i3c->regs, NTST, NTST_TDBEF0);
> + } else {
> + i3c_writel_fifo(i3c->regs + NTDTBP0, cmd->tx_buf, cmd->len);
> + }
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t renesas_i3c_resp_isr(int irq, void *data)
> +{
> + struct renesas_i3c *i3c = data;
> + struct renesas_i3c_xfer *xfer;
> + struct renesas_i3c_cmd *cmd;
> + u32 resp_descriptor = i3c_reg_read(i3c->regs, NRSPQP);
> + u32 bytes_remaining = 0;
> + u32 ntst, data_len;
> + int ret = 0;
> +
> + scoped_guard(spinlock, &i3c->xferqueue.lock) {
> + xfer = i3c->xferqueue.cur;
> + cmd = xfer->cmds;
> +
> + /* Clear the Respone Queue Full status flag*/
> + i3c_reg_clear_bit(i3c->regs, NTST, NTST_RSPQFF);
> +
> + data_len = NRSPQP_DATA_LEN(resp_descriptor);
> +
> + switch (i3c->internal_state) {
> + case I3C_INTERNAL_STATE_CONTROLLER_ENTDAA:
> + cmd->rx_count = data_len;
> + break;
> + case I3C_INTERNAL_STATE_CONTROLLER_WRITE:
> + case I3C_INTERNAL_STATE_CONTROLLER_COMMAND_WRITE:
> + /* Disable the transmit IRQ if it hasn't been disabled already. */
> + i3c_reg_clear_bit(i3c->regs, NTIE, NTIE_TDBEIE0);
> + break;
> + case I3C_INTERNAL_STATE_CONTROLLER_READ:
> + case I3C_INTERNAL_STATE_CONTROLLER_COMMAND_READ:
> + if (NDBSTLV0_RDBLV(i3c_reg_read(i3c->regs, NDBSTLV0)) && !cmd->err)
> + bytes_remaining = data_len - cmd->rx_count;
> +
> + i3c_readl_fifo(i3c->regs + NTDTBP0, cmd->rx_buf, bytes_remaining);
> + i3c_reg_clear_bit(i3c->regs, NTIE, NTIE_RDBFIE0);
> + break;
> + default:
> + break;
> + }
> +
> + switch (NRSPQP_ERR_STATUS(resp_descriptor)) {
> + case NRSPQP_NO_ERROR:
> + break;
> + case NRSPQP_ERROR_PARITY:
> + case NRSPQP_ERROR_IBA_NACK:
> + case NRSPQP_ERROR_TRANSF_ABORT:
> + case NRSPQP_ERROR_CRC:
> + case NRSPQP_ERROR_FRAME:
> + ret = -EIO;
> + break;
> + case NRSPQP_ERROR_OVER_UNDER_FLOW:
> + ret = -ENOSPC;
> + break;
> + case NRSPQP_ERROR_UNSUPPORTED:
> + ret = -EOPNOTSUPP;
> + break;
> + case NRSPQP_ERROR_I2C_W_NACK_ERR:
> + case NRSPQP_ERROR_ADDRESS_NACK:
> + default:
> + ret = -EINVAL;
> + break;
> + }
> +
> + /*
> + * If the transfer was aborted, then the abort flag must be cleared
> + * before notifying the application that a transfer has completed.
> + */
> + ntst = i3c_reg_read(i3c->regs, NTST);
> + if (ntst & NTST_TABTF)
> + i3c_reg_clear_bit(i3c->regs, BCTL, BCTL_ABT);
> +
> + /* Clear error status flags. */
> + i3c_reg_clear_bit(i3c->regs, NTST, NTST_TEF | NTST_TABTF);
> +
> + xfer->ret = ret;
> + complete(&xfer->comp);
> +
> + xfer = list_first_entry_or_null(&i3c->xferqueue.list,
> + struct renesas_i3c_xfer, node);
> + if (xfer)
> + list_del_init(&xfer->node);
> +
> + i3c->xferqueue.cur = xfer;
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t renesas_i3c_tend_isr(int irq, void *data)
> +{
> + struct renesas_i3c *i3c = data;
> + struct renesas_i3c_xfer *xfer;
> + struct renesas_i3c_cmd *cmd;
> +
> + scoped_guard(spinlock, &i3c->xferqueue.lock) {
> + xfer = i3c->xferqueue.cur;
> + cmd = xfer->cmds;
> +
> + if (xfer->is_i2c_xfer) {
> + if (i3c_reg_read(i3c->regs, BST) & BST_NACKDF) {
> + /* We got a NACKIE */
> + i3c_reg_read(i3c->regs, NTDTBP0); /* dummy read */
> + i3c_reg_clear_bit(i3c->regs, BST, BST_NACKDF);
> + cmd->err = -ENXIO;
> + } else if (cmd->i2c_bytes_left) {
> + i3c_reg_set_bit(i3c->regs, NTIE, NTIE_TDBEIE0);
> + return IRQ_NONE;
> + }
> +
> + if (cmd->i2c_is_last || cmd->err) {
> + i3c_reg_clear_bit(i3c->regs, BIE, BIE_TENDIE);
> + i3c_reg_set_bit(i3c->regs, BIE, BIE_SPCNDDIE);
> + i3c_reg_set_bit(i3c->regs, CNDCTL, CNDCTL_SPCND);
> + } else {
> + /* Transfer is complete, but do not send STOP */
> + i3c_reg_clear_bit(i3c->regs, NTSTE, NTSTE_TDBEE0);
> + i3c_reg_clear_bit(i3c->regs, BIE, BIE_TENDIE);
> + xfer->ret = 0;
> + complete(&xfer->comp);
> + }
> + }
> +
> + /* Clear the Transmit Buffer Empty status flag. */
> + i3c_reg_clear_bit(i3c->regs, BST, BST_TENDF);
Are you sure you can clear FIFO empty status? Generally it is read only.
Frank
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t renesas_i3c_rx_isr(int irq, void *data)
> +{
> + struct renesas_i3c *i3c = data;
> + struct renesas_i3c_xfer *xfer;
> + struct renesas_i3c_cmd *cmd;
> + int read_bytes;
> +
> + /* If resp_isr already read the data and updated 'xfer', we can just leave */
> + if (!(i3c_reg_read(i3c->regs, NTIE) & NTIE_RDBFIE0))
> + return IRQ_NONE;
> +
> + scoped_guard(spinlock, &i3c->xferqueue.lock) {
> + xfer = i3c->xferqueue.cur;
> + cmd = xfer->cmds;
> +
> + if (xfer->is_i2c_xfer) {
> + if (!cmd->i2c_bytes_left)
> + return IRQ_NONE;
> +
> + if (cmd->i2c_bytes_left == I2C_INIT_MSG) {
> + cmd->i2c_bytes_left = cmd->msg->len;
> + i3c_reg_set_bit(i3c->regs, SCSTRCTL, SCSTRCTL_RWE);
> + i3c_reg_read(i3c->regs, NTDTBP0); /* dummy read */
> + if (cmd->i2c_bytes_left == 1)
> + i3c_reg_write(i3c->regs, ACKCTL, ACKCTL_ACKT | ACKCTL_ACKTWP);
> + return IRQ_HANDLED;
> + }
> +
> + if (cmd->i2c_bytes_left == 1) {
> + /* STOP must come before we set ACKCTL! */
> + if (cmd->i2c_is_last) {
> + i3c_reg_set_bit(i3c->regs, BIE, BIE_SPCNDDIE);
> + i3c_reg_clear_bit(i3c->regs, BST, BST_SPCNDDF);
> + i3c_reg_set_bit(i3c->regs, CNDCTL, CNDCTL_SPCND);
> + }
> + i3c_reg_write(i3c->regs, ACKCTL, ACKCTL_ACKT | ACKCTL_ACKTWP);
> + } else {
> + i3c_reg_write(i3c->regs, ACKCTL, ACKCTL_ACKTWP);
> + }
> +
> + /* Reading acks the RIE interrupt */
> + *cmd->i2c_buf = i3c_reg_read(i3c->regs, NTDTBP0);
> + cmd->i2c_buf++;
> + cmd->i2c_bytes_left--;
> + } else {
> + read_bytes = NDBSTLV0_RDBLV(i3c_reg_read(i3c->regs, NDBSTLV0)) * sizeof(u32);
> + i3c_readl_fifo(i3c->regs + NTDTBP0, cmd->rx_buf, read_bytes);
> + cmd->rx_count = read_bytes;
> + }
> +
> + /* Clear the Read Buffer Full status flag. */
> + i3c_reg_clear_bit(i3c->regs, NTST, NTST_RDBFF0);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t renesas_i3c_stop_isr(int irq, void *data)
> +{
> + struct renesas_i3c *i3c = data;
> + struct renesas_i3c_xfer *xfer;
> +
> + scoped_guard(spinlock, &i3c->xferqueue.lock) {
> + xfer = i3c->xferqueue.cur;
> +
> + /* read back registers to confirm writes have fully propagated */
> + i3c_reg_write(i3c->regs, BST, 0);
> + i3c_reg_read(i3c->regs, BST);
> + i3c_reg_write(i3c->regs, BIE, 0);
> + i3c_reg_clear_bit(i3c->regs, NTST, NTST_TDBEF0 | NTST_RDBFF0);
> + i3c_reg_clear_bit(i3c->regs, SCSTRCTL, SCSTRCTL_RWE);
> +
> + xfer->ret = 0;
> + complete(&xfer->comp);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t renesas_i3c_start_isr(int irq, void *data)
> +{
> + struct renesas_i3c *i3c = data;
> + struct renesas_i3c_xfer *xfer;
> + struct renesas_i3c_cmd *cmd;
> + u8 val;
> +
> + scoped_guard(spinlock, &i3c->xferqueue.lock) {
> + xfer = i3c->xferqueue.cur;
> + cmd = xfer->cmds;
> +
> + if (xfer->is_i2c_xfer) {
> + if (!cmd->i2c_bytes_left)
> + return IRQ_NONE;
> +
> + if (cmd->i2c_bytes_left == I2C_INIT_MSG) {
> + if (cmd->msg->flags & I2C_M_RD) {
> + /* On read, switch over to receive interrupt */
> + i3c_reg_clear_bit(i3c->regs, NTIE, NTIE_TDBEIE0);
> + i3c_reg_set_bit(i3c->regs, NTIE, NTIE_RDBFIE0);
> + } else {
> + /* On write, initialize length */
> + cmd->i2c_bytes_left = cmd->msg->len;
> + }
> +
> + val = i2c_8bit_addr_from_msg(cmd->msg);
> + i3c_reg_write(i3c->regs, NTDTBP0, val);
> + }
> + }
> +
> + i3c_reg_clear_bit(i3c->regs, BIE, BIE_STCNDDIE);
> + i3c_reg_clear_bit(i3c->regs, BST, BST_STCNDDF);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static const struct i3c_master_controller_ops renesas_i3c_ops = {
> + .bus_init = renesas_i3c_bus_init,
> + .bus_cleanup = renesas_i3c_bus_cleanup,
> + .attach_i3c_dev = renesas_i3c_attach_i3c_dev,
> + .reattach_i3c_dev = renesas_i3c_reattach_i3c_dev,
> + .detach_i3c_dev = renesas_i3c_detach_i3c_dev,
> + .do_daa = renesas_i3c_daa,
> + .supports_ccc_cmd = renesas_i3c_supports_ccc_cmd,
> + .send_ccc_cmd = renesas_i3c_send_ccc_cmd,
> + .priv_xfers = renesas_i3c_priv_xfers,
> + .attach_i2c_dev = renesas_i3c_attach_i2c_dev,
> + .detach_i2c_dev = renesas_i3c_detach_i2c_dev,
> + .i2c_xfers = renesas_i3c_i2c_xfers,
> +};
> +
> +static struct renesas_i3c_irq_desc renesas_i3c_irqs[] = {
> + { .name = "resp", .isr = renesas_i3c_resp_isr, .desc = "i3c-resp" },
> + { .name = "rx", .isr = renesas_i3c_rx_isr, .desc = "i3c-rx" },
> + { .name = "tx", .isr = renesas_i3c_tx_isr, .desc = "i3c-tx" },
> + { .name = "st", .isr = renesas_i3c_start_isr, .desc = "i3c-start" },
> + { .name = "sp", .isr = renesas_i3c_stop_isr, .desc = "i3c-stop" },
> + { .name = "tend", .isr = renesas_i3c_tend_isr, .desc = "i3c-tend" },
> + { .name = "nack", .isr = renesas_i3c_tend_isr, .desc = "i3c-nack" },
> +};
> +
> +static int renesas_i3c_probe(struct platform_device *pdev)
> +{
> + struct renesas_i3c *i3c;
> + struct reset_control *reset;
> + struct clk *clk;
> + const struct renesas_i3c_config *config = of_device_get_match_data(&pdev->dev);
> + int ret, i;
> +
> + if (!config)
> + return -ENODATA;
> +
> + i3c = devm_kzalloc(&pdev->dev, sizeof(*i3c), GFP_KERNEL);
> + if (!i3c)
> + return -ENOMEM;
> +
> + i3c->regs = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(i3c->regs))
> + return PTR_ERR(i3c->regs);
> +
> + clk = devm_clk_get_enabled(&pdev->dev, "pclk");
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
> +
> + if (config->has_pclkrw) {
> + clk = devm_clk_get_enabled(&pdev->dev, "pclkrw");
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
> + }
> +
> + i3c->tclk = devm_clk_get_enabled(&pdev->dev, "tclk");
> + if (IS_ERR(i3c->tclk))
> + return PTR_ERR(i3c->tclk);
> +
> + reset = devm_reset_control_get_optional_exclusive_deasserted(&pdev->dev, "tresetn");
> + if (IS_ERR(reset))
> + return dev_err_probe(&pdev->dev, PTR_ERR(reset),
> + "Error: missing tresetn ctrl\n");
> +
> + reset = devm_reset_control_get_optional_exclusive_deasserted(&pdev->dev, "presetn");
> + if (IS_ERR(reset))
> + return dev_err_probe(&pdev->dev, PTR_ERR(reset),
> + "Error: missing presetn ctrl\n");
> +
> + spin_lock_init(&i3c->xferqueue.lock);
> + INIT_LIST_HEAD(&i3c->xferqueue.list);
> +
> + ret = renesas_i3c_reset(i3c);
> + if (ret)
> + return ret;
> +
> + for (i = 0; i < ARRAY_SIZE(renesas_i3c_irqs); i++) {
> + ret = platform_get_irq_byname(pdev, renesas_i3c_irqs[i].name);
> + if (ret < 0)
> + return ret;
> +
> + ret = devm_request_irq(&pdev->dev, ret, renesas_i3c_irqs[i].isr,
> + 0, renesas_i3c_irqs[i].desc, i3c);
> + if (ret)
> + return ret;
> + }
> +
> + platform_set_drvdata(pdev, i3c);
> +
> + i3c->maxdevs = RENESAS_I3C_MAX_DEVS;
> + i3c->free_pos = GENMASK(i3c->maxdevs - 1, 0);
> +
> + return i3c_master_register(&i3c->base, &pdev->dev, &renesas_i3c_ops, false);
> +}
> +
> +static void renesas_i3c_remove(struct platform_device *pdev)
> +{
> + struct renesas_i3c *i3c = platform_get_drvdata(pdev);
> +
> + i3c_master_unregister(&i3c->base);
> +}
> +
> +static const struct renesas_i3c_config empty_i3c_config = {
> +};
> +
> +static const struct renesas_i3c_config r9a09g047_i3c_config = {
> + .has_pclkrw = 1,
> +};
> +
> +static const struct of_device_id renesas_i3c_of_ids[] = {
> + { .compatible = "renesas,r9a08g045-i3c", .data = &empty_i3c_config },
> + { .compatible = "renesas,r9a09g047-i3c", .data = &r9a09g047_i3c_config },
> + { .compatible = "renesas,i3c", .data = &empty_i3c_config },
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, renesas_i3c_of_ids);
> +
> +static struct platform_driver renesas_i3c = {
> + .probe = renesas_i3c_probe,
> + .remove = renesas_i3c_remove,
> + .driver = {
> + .name = "renesas-i3c",
> + .of_match_table = renesas_i3c_of_ids,
> + },
> +};
> +module_platform_driver(renesas_i3c);
> +
> +MODULE_AUTHOR("Wolfram Sang <wsa+renesas at sang-engineering.com>");
> +MODULE_AUTHOR("Renesas BSP teams");
> +MODULE_DESCRIPTION("Renesas I3C controller driver");
> +MODULE_LICENSE("GPL");
> --
> 2.47.2
>
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