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i2c: viai2c: turn common code into a proper module

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The i2c-viai2c-common.c file is used by two drivers, but is not a proper
abstraction and can get linked into both modules in the same configuration,
which results in a warning:

scripts/Makefile.build:236: drivers/i2c/busses/Makefile: i2c-viai2c-common.o is added to multiple modules: i2c-wmt i2c-zhaoxin

The other problems with this include the incorrect use of a __weak function
when both are built-in, and the fact that the "common" module is sprinked
with 'if (i2c->plat == ...)' checks that have knowledge about the differences
between the drivers using it.

Avoid the link time warning by making the common driver a proper module
with MODULE_LICENCE()/MODULE_AUTHOR() tags, and remove the __weak function
by slightly rearranging the code.

This adds a little more duplication between the two main drivers, but
those versions get more readable in the process.

Fixes: a06b80e830 ("i2c: add zhaoxin i2c controller driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Hans Hu <HansHu-oc@zhaoxin.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
This commit is contained in:
Arnd Bergmann 2024-05-28 14:06:30 +02:00 committed by Andi Shyti
parent f2661062f1
commit 103458874b
5 changed files with 140 additions and 90 deletions
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6
drivers/i2c/busses/Makefile
View File

@ -29,8 +29,7 @@ obj-$(CONFIG_I2C_SIS630) += i2c-sis630.o
obj-$(CONFIG_I2C_SIS96X) += i2c-sis96x.o
obj-$(CONFIG_I2C_VIA) += i2c-via.o
obj-$(CONFIG_I2C_VIAPRO) += i2c-viapro.o
i2c-zhaoxin-objs := i2c-viai2c-zhaoxin.o i2c-viai2c-common.o
obj-$(CONFIG_I2C_ZHAOXIN) += i2c-zhaoxin.o
obj-$(CONFIG_I2C_ZHAOXIN) += i2c-viai2c-zhaoxin.o i2c-viai2c-common.o
# Mac SMBus host controller drivers
obj-$(CONFIG_I2C_HYDRA) += i2c-hydra.o
@ -120,8 +119,7 @@ obj-$(CONFIG_I2C_TEGRA_BPMP) += i2c-tegra-bpmp.o
obj-$(CONFIG_I2C_UNIPHIER) += i2c-uniphier.o
obj-$(CONFIG_I2C_UNIPHIER_F) += i2c-uniphier-f.o
obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o
i2c-wmt-objs := i2c-viai2c-wmt.o i2c-viai2c-common.o
obj-$(CONFIG_I2C_WMT) += i2c-wmt.o
obj-$(CONFIG_I2C_WMT) += i2c-viai2c-wmt.o i2c-viai2c-common.o
i2c-octeon-objs := i2c-octeon-core.o i2c-octeon-platdrv.o
obj-$(CONFIG_I2C_OCTEON) += i2c-octeon.o
i2c-thunderx-objs := i2c-octeon-core.o i2c-thunderx-pcidrv.o

71
drivers/i2c/busses/i2c-viai2c-common.c
View File

@ -17,6 +17,7 @@ int viai2c_wait_bus_not_busy(struct viai2c *i2c)
return 0;
}
EXPORT_SYMBOL_GPL(viai2c_wait_bus_not_busy);
static int viai2c_write(struct viai2c *i2c, struct i2c_msg *pmsg, int last)
{
@ -121,6 +122,7 @@ int viai2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
return (ret < 0) ? ret : i;
}
EXPORT_SYMBOL_GPL(viai2c_xfer);
/*
* Main process of the byte mode xfer
@ -130,7 +132,7 @@ int viai2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
* 0: there is still data that needs to be transferred
* -EIO: error occurred
*/
static int viai2c_irq_xfer(struct viai2c *i2c)
int viai2c_irq_xfer(struct viai2c *i2c)
{
u16 val;
struct i2c_msg *msg = i2c->msg;
@ -171,51 +173,11 @@ static int viai2c_irq_xfer(struct viai2c *i2c)
return i2c->xfered_len == msg->len;
}
int __weak viai2c_fifo_irq_xfer(struct viai2c *i2c, bool irq)
{
return 0;
}
static irqreturn_t viai2c_isr(int irq, void *data)
{
struct viai2c *i2c = data;
u8 status;
/* save the status and write-clear it */
status = readw(i2c->base + VIAI2C_REG_ISR);
if (!status && i2c->platform == VIAI2C_PLAT_ZHAOXIN)
return IRQ_NONE;
writew(status, i2c->base + VIAI2C_REG_ISR);
i2c->ret = 0;
if (status & VIAI2C_ISR_NACK_ADDR)
i2c->ret = -EIO;
if (i2c->platform == VIAI2C_PLAT_WMT && (status & VIAI2C_ISR_SCL_TIMEOUT))
i2c->ret = -ETIMEDOUT;
if (!i2c->ret) {
if (i2c->mode == VIAI2C_BYTE_MODE)
i2c->ret = viai2c_irq_xfer(i2c);
else
i2c->ret = viai2c_fifo_irq_xfer(i2c, true);
}
/* All the data has been successfully transferred or error occurred */
if (i2c->ret)
complete(&i2c->complete);
return IRQ_HANDLED;
}
EXPORT_SYMBOL_GPL(viai2c_irq_xfer);
int viai2c_init(struct platform_device *pdev, struct viai2c **pi2c, int plat)
{
int err;
int irq_flags;
struct viai2c *i2c;
struct device_node *np = pdev->dev.of_node;
i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
if (!i2c)
@ -225,28 +187,8 @@ int viai2c_init(struct platform_device *pdev, struct viai2c **pi2c, int plat)
if (IS_ERR(i2c->base))
return PTR_ERR(i2c->base);
if (plat == VIAI2C_PLAT_WMT) {
irq_flags = 0;
i2c->irq = irq_of_parse_and_map(np, 0);
if (!i2c->irq)
return -EINVAL;
} else if (plat == VIAI2C_PLAT_ZHAOXIN) {
irq_flags = IRQF_SHARED;
i2c->irq = platform_get_irq(pdev, 0);
if (i2c->irq < 0)
return i2c->irq;
} else {
return dev_err_probe(&pdev->dev, -EINVAL, "wrong platform type\n");
}
i2c->platform = plat;
err = devm_request_irq(&pdev->dev, i2c->irq, viai2c_isr,
irq_flags, pdev->name, i2c);
if (err)
return dev_err_probe(&pdev->dev, err,
"failed to request irq %i\n", i2c->irq);
i2c->dev = &pdev->dev;
init_completion(&i2c->complete);
platform_set_drvdata(pdev, i2c);
@ -254,3 +196,8 @@ int viai2c_init(struct platform_device *pdev, struct viai2c **pi2c, int plat)
*pi2c = i2c;
return 0;
}
EXPORT_SYMBOL_GPL(viai2c_init);
MODULE_DESCRIPTION("Via/Wondermedia/Zhaoxin I2C master-mode bus adapter");
MODULE_AUTHOR("Tony Prisk <linux@prisktech.co.nz>");
MODULE_LICENSE("GPL");

2
drivers/i2c/busses/i2c-viai2c-common.h
View File

@ -80,6 +80,6 @@ struct viai2c {
int viai2c_wait_bus_not_busy(struct viai2c *i2c);
int viai2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num);
int viai2c_init(struct platform_device *pdev, struct viai2c **pi2c, int plat);
int viai2c_fifo_irq_xfer(struct viai2c *i2c, bool irq);
int viai2c_irq_xfer(struct viai2c *i2c);
#endif

36
drivers/i2c/busses/i2c-viai2c-wmt.c
View File

@ -72,6 +72,32 @@ static int wmt_i2c_reset_hardware(struct viai2c *i2c)
return 0;
}
static irqreturn_t wmt_i2c_isr(int irq, void *data)
{
struct viai2c *i2c = data;
u8 status;
/* save the status and write-clear it */
status = readw(i2c->base + VIAI2C_REG_ISR);
writew(status, i2c->base + VIAI2C_REG_ISR);
i2c->ret = 0;
if (status & VIAI2C_ISR_NACK_ADDR)
i2c->ret = -EIO;
if (status & VIAI2C_ISR_SCL_TIMEOUT)
i2c->ret = -ETIMEDOUT;
if (!i2c->ret)
i2c->ret = viai2c_irq_xfer(i2c);
/* All the data has been successfully transferred or error occurred */
if (i2c->ret)
complete(&i2c->complete);
return IRQ_HANDLED;
}
static int wmt_i2c_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
@ -84,6 +110,16 @@ static int wmt_i2c_probe(struct platform_device *pdev)
if (err)
return err;
i2c->irq = platform_get_irq(pdev, 0);
if (i2c->irq < 0)
return i2c->irq;
err = devm_request_irq(&pdev->dev, i2c->irq, wmt_i2c_isr,
0, pdev->name, i2c);
if (err)
return dev_err_probe(&pdev->dev, err,
"failed to request irq %i\n", i2c->irq);
i2c->clk = of_clk_get(np, 0);
if (IS_ERR(i2c->clk)) {
dev_err(&pdev->dev, "unable to request clock\n");

115
drivers/i2c/busses/i2c-viai2c-zhaoxin.c
View File

@ -49,8 +49,7 @@ struct viai2c_zhaoxin {
u16 xfer_len;
};
/* 'irq == true' means in interrupt context */
int viai2c_fifo_irq_xfer(struct viai2c *i2c, bool irq)
static int viai2c_fifo_xfer(struct viai2c *i2c)
{
u16 i;
u8 tmp;
@ -59,17 +58,6 @@ int viai2c_fifo_irq_xfer(struct viai2c *i2c, bool irq)
bool read = !!(msg->flags & I2C_M_RD);
struct viai2c_zhaoxin *priv = i2c->pltfm_priv;
if (irq) {
/* get the received data */
if (read)
for (i = 0; i < priv->xfer_len; i++)
msg->buf[i2c->xfered_len + i] = ioread8(base + ZXI2C_REG_HRDR);
i2c->xfered_len += priv->xfer_len;
if (i2c->xfered_len == msg->len)
return 1;
}
/* reset fifo buffer */
tmp = ioread8(base + ZXI2C_REG_HCR);
iowrite8(tmp | ZXI2C_HCR_RST_FIFO, base + ZXI2C_REG_HCR);
@ -92,18 +80,59 @@ int viai2c_fifo_irq_xfer(struct viai2c *i2c, bool irq)
iowrite8(tmp, base + VIAI2C_REG_CR);
}
if (irq) {
/* continue transmission */
tmp = ioread8(base + VIAI2C_REG_CR);
iowrite8(tmp |= VIAI2C_CR_CPU_RDY, base + VIAI2C_REG_CR);
} else {
u16 tcr_val = i2c->tcr;
u16 tcr_val = i2c->tcr;
/* start transmission */
tcr_val |= read ? VIAI2C_TCR_READ : 0;
writew(tcr_val | msg->addr, base + VIAI2C_REG_TCR);
/* start transmission */
tcr_val |= read ? VIAI2C_TCR_READ : 0;
writew(tcr_val | msg->addr, base + VIAI2C_REG_TCR);
return 0;
}
static int viai2c_fifo_irq_xfer(struct viai2c *i2c)
{
u16 i;
u8 tmp;
struct i2c_msg *msg = i2c->msg;
void __iomem *base = i2c->base;
bool read = !!(msg->flags & I2C_M_RD);
struct viai2c_zhaoxin *priv = i2c->pltfm_priv;
/* get the received data */
if (read)
for (i = 0; i < priv->xfer_len; i++)
msg->buf[i2c->xfered_len + i] = ioread8(base + ZXI2C_REG_HRDR);
i2c->xfered_len += priv->xfer_len;
if (i2c->xfered_len == msg->len)
return 1;
/* reset fifo buffer */
tmp = ioread8(base + ZXI2C_REG_HCR);
iowrite8(tmp | ZXI2C_HCR_RST_FIFO, base + ZXI2C_REG_HCR);
/* set xfer len */
priv->xfer_len = min_t(u16, msg->len - i2c->xfered_len, ZXI2C_FIFO_SIZE);
if (read) {
iowrite8(priv->xfer_len - 1, base + ZXI2C_REG_HRLR);
} else {
iowrite8(priv->xfer_len - 1, base + ZXI2C_REG_HTLR);
/* set write data */
for (i = 0; i < priv->xfer_len; i++)
iowrite8(msg->buf[i2c->xfered_len + i], base + ZXI2C_REG_HTDR);
}
/* prepare to stop transmission */
if (priv->hrv && msg->len == (i2c->xfered_len + priv->xfer_len)) {
tmp = ioread8(base + VIAI2C_REG_CR);
tmp |= read ? VIAI2C_CR_RX_END : VIAI2C_CR_TX_END;
iowrite8(tmp, base + VIAI2C_REG_CR);
}
/* continue transmission */
tmp = ioread8(base + VIAI2C_REG_CR);
iowrite8(tmp |= VIAI2C_CR_CPU_RDY, base + VIAI2C_REG_CR);
return 0;
}
@ -135,7 +164,7 @@ static int zxi2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int
priv->xfer_len = 0;
i2c->xfered_len = 0;
viai2c_fifo_irq_xfer(i2c, 0);
viai2c_fifo_xfer(i2c);
if (!wait_for_completion_timeout(&i2c->complete, VIAI2C_TIMEOUT))
return -ETIMEDOUT;
@ -228,6 +257,36 @@ static void zxi2c_get_bus_speed(struct viai2c *i2c)
dev_info(i2c->dev, "speed mode is %s\n", i2c_freq_mode_string(params[0]));
}
static irqreturn_t zxi2c_isr(int irq, void *data)
{
struct viai2c *i2c = data;
u8 status;
/* save the status and write-clear it */
status = readw(i2c->base + VIAI2C_REG_ISR);
if (!status)
return IRQ_NONE;
writew(status, i2c->base + VIAI2C_REG_ISR);
i2c->ret = 0;
if (status & VIAI2C_ISR_NACK_ADDR)
i2c->ret = -EIO;
if (!i2c->ret) {
if (i2c->mode == VIAI2C_BYTE_MODE)
i2c->ret = viai2c_irq_xfer(i2c);
else
i2c->ret = viai2c_fifo_irq_xfer(i2c);
}
/* All the data has been successfully transferred or error occurred */
if (i2c->ret)
complete(&i2c->complete);
return IRQ_HANDLED;
}
static int zxi2c_probe(struct platform_device *pdev)
{
int error;
@ -239,6 +298,16 @@ static int zxi2c_probe(struct platform_device *pdev)
if (error)
return error;
i2c->irq = platform_get_irq(pdev, 0);
if (i2c->irq < 0)
return i2c->irq;
error = devm_request_irq(&pdev->dev, i2c->irq, zxi2c_isr,
IRQF_SHARED, pdev->name, i2c);
if (error)
return dev_err_probe(&pdev->dev, error,
"failed to request irq %i\n", i2c->irq);
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;