[i2c] [PATCH] basic gpio_chip support for 16-bit PCA9539 GPIO expander
Jean Delvare
khali at linux-fr.org
Mon Dec 3 16:42:22 CET 2007
Hi Eric,
On Mon, 3 Dec 2007 19:01:26 +0800, eric miao wrote:
> On Dec 3, 2007 5:12 PM, David Brownell <david-b at pacbell.net> wrote:
> > Kconfig needs to say that it depends on GPIO_LIB...
> >
> > And none of the IRQ logic should be included in modular builds;
> > see below.
> >
> > - Dave
> >
>
> Indeed, sorry for this. Updated, please review, thx.
Only stylistic comments:
>
> From 4e79cf08d4f75fbc713cf8840aac05e31e65993f Mon Sep 17 00:00:00 2001
> From: eric miao <eric.miao at marvell.com>
> Date: Thu, 29 Nov 2007 09:44:57 +0800
> Subject: [PATCH] pxa: basic gpio_chip support for 16-bit PCA9539 GPIO expander
>
> 1. make the original pca9539 driver to use the new style I2C driver
> model
>
> 2. use "struct gpio_chip" so that PCA9539 can be used by Generic GPIO
> API
>
> 3. add "struct irq_chip" support for on-chip IRQs, due to the interrupt
> based I2C transfer, the IRQ handlers are actually performed within
> workqueue
>
> 4. remove sysfs entries to avoid register access conflict with Generic
> GPIO/IRQ support (assuming that no one is ever using these entries)
>
> 5. use 2 x 8-bit register access to simplify the logic, cache OUTPUT
> and DIRECTION registers for fast access
>
> 6. platform code is required to setup
> a) the numbering of GPIO/IRQ for PCA9539
> b) the mapping between these GPIOs and IRQs
> i.e. keep correct gpio_to_irq()/irq_to_gpio()
> c) pass "pca9539_platform_data" within "i2c_board_info"
>
> Signed-off-by: eric miao <eric.miao at marvell.com>
> ---
> Documentation/i2c/chips/pca9539 | 36 ++--
> drivers/i2c/chips/Kconfig | 2 +-
> drivers/i2c/chips/pca9539.c | 456 ++++++++++++++++++++++++++++-----------
> include/linux/pca9539.h | 18 ++
> 4 files changed, 361 insertions(+), 151 deletions(-)
> create mode 100644 include/linux/pca9539.h
>
> diff --git a/Documentation/i2c/chips/pca9539 b/Documentation/i2c/chips/pca9539
> index c4fce6a..8426696 100644
> --- a/Documentation/i2c/chips/pca9539
> +++ b/Documentation/i2c/chips/pca9539
> @@ -19,29 +19,23 @@ All 16 lines can be individually configured as an
> input or output.
Note: Your mailer is wrapping long lines, so I had to fix the patch
manually before I could apply it.
> The input sense can also be inverted.
> The 16 lines are split between two bytes.
>
> +Generic GPIO support
> +--------------------
>
> -Sysfs entries
> --------------
> -
> -Each is a byte that maps to the 8 I/O bits.
> -A '0' suffix is for bits 0-7, while '1' is for bits 8-15.
> -
> -input[01] - read the current value
> -output[01] - sets the output value
> -direction[01] - direction of each bit: 1=input, 0=output
> -invert[01] - toggle the input bit sense
> +The extended I/O ports are now fully covered by Generic GPIO API with
> +GPIO lib support. The "struct pca9539_platform_data" has to be filled
> +by platform specific code to properly initialize the PCA9539.
>
> -input reads the actual state of the line and is always available.
> -The direction defaults to input for all channels.
> +Generic IRQ support
> +-------------------
>
> +Each of the 16 I/O ports can also be used as cascaded IRQ line. Unlike
> +normal IRQs, the IRQ handler code for PCA9539 is actually executed by
Doubled space.
> +work queue to avoid I2C transactions to be performed within interrupt
> +context.
>
> -General Remarks
> ----------------
> -
> -Note that each output, direction, and invert entry controls 8 lines.
> -You should use the read, modify, write sequence.
> -For example. to set output bit 0 of 1.
> - val=$(cat output0)
> - val=$(( $val | 1 ))
> - echo $val > output0
> +Sysfs entries
> +-------------
>
> +The original sysfs entries are removed to avoid register access conflict
> +with the Generic GPIO/IRQ support.
> diff --git a/drivers/i2c/chips/Kconfig b/drivers/i2c/chips/Kconfig
> index 2e1c24f..90f1064 100644
> --- a/drivers/i2c/chips/Kconfig
> +++ b/drivers/i2c/chips/Kconfig
> @@ -67,7 +67,7 @@ config SENSORS_PCF8574
>
> config SENSORS_PCA9539
> tristate "Philips PCA9539 16-bit I/O port"
> - depends on EXPERIMENTAL
> + depends on EXPERIMENTAL && GPIO_LIB
> help
> If you say yes here you get support for the Philips PCA9539
> 16-bit I/O port.
> diff --git a/drivers/i2c/chips/pca9539.c b/drivers/i2c/chips/pca9539.c
> index f43c4e7..de64e27 100644
> --- a/drivers/i2c/chips/pca9539.c
> +++ b/drivers/i2c/chips/pca9539.c
> @@ -2,6 +2,7 @@
> pca9539.c - 16-bit I/O port with interrupt and reset
>
> Copyright (C) 2005 Ben Gardner <bgardner at wabtec.com>
> + Copyright (C) 2007 Marvell Internation Ltd.
>
> This program is free software; you can redistribute it and/or modify
> it under the terms of the GNU General Public License as published by
> @@ -10,173 +11,371 @@
>
> #include <linux/module.h>
> #include <linux/init.h>
> -#include <linux/slab.h>
> +#include <linux/irq.h>
> +#include <linux/interrupt.h>
> +#include <linux/workqueue.h>
> #include <linux/i2c.h>
> -#include <linux/hwmon-sysfs.h>
> +#include <linux/pca9539.h>
>
> -/* Addresses to scan */
> -static unsigned short normal_i2c[] = {0x74, 0x75, 0x76, 0x77, I2C_CLIENT_END};
> +#include <asm/gpio.h>
>
> -/* Insmod parameters */
> -I2C_CLIENT_INSMOD_1(pca9539);
> +#define NR_PCA9539_GPIOS 16
>
> -enum pca9539_cmd
> -{
> - PCA9539_INPUT_0 = 0,
> - PCA9539_INPUT_1 = 1,
> - PCA9539_OUTPUT_0 = 2,
> - PCA9539_OUTPUT_1 = 3,
> - PCA9539_INVERT_0 = 4,
> - PCA9539_INVERT_1 = 5,
> - PCA9539_DIRECTION_0 = 6,
> - PCA9539_DIRECTION_1 = 7,
> -};
> +#define PCA9539_INPUT 0
> +#define PCA9539_OUTPUT 2
> +#define PCA9539_INVERT 4
> +#define PCA9539_DIRECTION 6
>
> -static int pca9539_attach_adapter(struct i2c_adapter *adapter);
> -static int pca9539_detect(struct i2c_adapter *adapter, int address, int kind);
> -static int pca9539_detach_client(struct i2c_client *client);
> +struct pca9539_chip {
> + int irq;
>
> -/* This is the driver that will be inserted */
> -static struct i2c_driver pca9539_driver = {
> - .driver = {
> - .name = "pca9539",
> - },
> - .attach_adapter = pca9539_attach_adapter,
> - .detach_client = pca9539_detach_client,
> -};
> + unsigned gpio_start;
> + int irq_start;
>
> -struct pca9539_data {
> - struct i2c_client client;
> + uint16_t reg_output;
> + uint16_t reg_direction;
> +
> + uint16_t last_input;
> +
> + struct i2c_client *client;
> + struct gpio_chip gpio_chip;
> +
> +#ifndef MODULE
> + /*
> + * Note: Generic IRQ is not accessible within module code, the IRQ
> + * support will thus _only_ be present if the driver is built-in
> + */
Don't you think it would be worth mentioning in the documentation
and/or Kconfig?
> + uint16_t irq_mask;
> + uint16_t irq_falling_edge;
> + uint16_t irq_rising_edge;
> +
> + struct irq_chip irq_chip;
> + struct work_struct irq_work;
> +#endif
> };
>
> -/* following are the sysfs callback functions */
> -static ssize_t pca9539_show(struct device *dev, struct device_attribute *attr,
> - char *buf)
> +static int pca9539_write_reg(struct pca9539_chip *chip, int reg, uint16_t val)
> {
> - struct sensor_device_attribute *psa = to_sensor_dev_attr(attr);
> - struct i2c_client *client = to_i2c_client(dev);
> - return sprintf(buf, "%d\n", i2c_smbus_read_byte_data(client,
> - psa->index));
> + return i2c_smbus_write_word_data(chip->client, reg, val);
> }
>
> -static ssize_t pca9539_store(struct device *dev, struct device_attribute *attr,
> - const char *buf, size_t count)
> +static int pca9539_read_reg(struct pca9539_chip *chip, int reg, uint16_t *val)
> {
> - struct sensor_device_attribute *psa = to_sensor_dev_attr(attr);
> - struct i2c_client *client = to_i2c_client(dev);
> - unsigned long val = simple_strtoul(buf, NULL, 0);
> - if (val > 0xff)
> - return -EINVAL;
> - i2c_smbus_write_byte_data(client, psa->index, val);
> - return count;
> -}
> -
> -/* Define the device attributes */
> -
> -#define PCA9539_ENTRY_RO(name, cmd_idx) \
> - static SENSOR_DEVICE_ATTR(name, S_IRUGO, pca9539_show, NULL, cmd_idx)
> -
> -#define PCA9539_ENTRY_RW(name, cmd_idx) \
> - static SENSOR_DEVICE_ATTR(name, S_IRUGO | S_IWUSR, pca9539_show, \
> - pca9539_store, cmd_idx)
> -
> -PCA9539_ENTRY_RO(input0, PCA9539_INPUT_0);
> -PCA9539_ENTRY_RO(input1, PCA9539_INPUT_1);
> -PCA9539_ENTRY_RW(output0, PCA9539_OUTPUT_0);
> -PCA9539_ENTRY_RW(output1, PCA9539_OUTPUT_1);
> -PCA9539_ENTRY_RW(invert0, PCA9539_INVERT_0);
> -PCA9539_ENTRY_RW(invert1, PCA9539_INVERT_1);
> -PCA9539_ENTRY_RW(direction0, PCA9539_DIRECTION_0);
> -PCA9539_ENTRY_RW(direction1, PCA9539_DIRECTION_1);
> -
> -static struct attribute *pca9539_attributes[] = {
> - &sensor_dev_attr_input0.dev_attr.attr,
> - &sensor_dev_attr_input1.dev_attr.attr,
> - &sensor_dev_attr_output0.dev_attr.attr,
> - &sensor_dev_attr_output1.dev_attr.attr,
> - &sensor_dev_attr_invert0.dev_attr.attr,
> - &sensor_dev_attr_invert1.dev_attr.attr,
> - &sensor_dev_attr_direction0.dev_attr.attr,
> - &sensor_dev_attr_direction1.dev_attr.attr,
> - NULL
> -};
> + int ret;
>
> -static struct attribute_group pca9539_defattr_group = {
> - .attrs = pca9539_attributes,
> -};
> + ret = i2c_smbus_read_word_data(chip->client, reg);
> + if (ret < 0) {
> + printk(KERN_ERR "%s: failed to read\n", __FUNCTION__);
> + return ret;
> + }
> +
> + *val = (uint16_t)ret;
> + return 0;
> +}
> +
> +static int pca9539_gpio_direction_input(struct gpio_chip *gc, unsigned off)
> +{
> + struct pca9539_chip *chip;
> + uint16_t reg_val;
> + int ret;
> +
> + chip = container_of(gc, struct pca9539_chip, gpio_chip);
> +
> + reg_val = chip->reg_direction | (1u << off);
> + ret = pca9539_write_reg(chip, PCA9539_DIRECTION, reg_val);
> + if (ret)
> + return ret;
> +
> + chip->reg_direction = reg_val;
> + return 0;
> +}
> +
> +static int pca9539_gpio_direction_output(struct gpio_chip *gc,
> + unsigned off, int val)
> +{
> + struct pca9539_chip *chip;
> + uint16_t reg_val;
> + int ret;
>
> -static int pca9539_attach_adapter(struct i2c_adapter *adapter)
> + chip = container_of(gc, struct pca9539_chip, gpio_chip);
> +
> + /* set output level */
> + if (val)
> + reg_val = chip->reg_output | (1u << off);
> + else
> + reg_val = chip->reg_output & ~(1u << off);
> +
> + ret = pca9539_write_reg(chip, PCA9539_OUTPUT, reg_val);
> + if (ret)
> + return ret;
> +
> + chip->reg_output = reg_val;
> +
> + /* then direction */
> + reg_val = chip->reg_direction & ~(1u << off);
> + ret = pca9539_write_reg(chip, PCA9539_DIRECTION, reg_val);
> + if (ret)
> + return ret;
> +
> + chip->reg_direction = reg_val;
> + return 0;
> +}
> +
> +static int pca9539_gpio_get_value(struct gpio_chip *gc, unsigned off)
> {
> - return i2c_probe(adapter, &addr_data, pca9539_detect);
> + struct pca9539_chip *chip;
> + uint16_t reg_val;
> + int ret;
> +
> + chip = container_of(gc, struct pca9539_chip, gpio_chip);
> +
> + ret = pca9539_read_reg(chip, PCA9539_INPUT, ®_val);
> + if (ret < 0)
> + return ret;
> +
> + return (reg_val & (1u << off)) ? 1 : 0;
> }
>
> -/* This function is called by i2c_probe */
> -static int pca9539_detect(struct i2c_adapter *adapter, int address, int kind)
> +static void pca9539_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
> {
> - struct i2c_client *new_client;
> - struct pca9539_data *data;
> - int err = 0;
> + struct pca9539_chip *chip;
> + uint16_t reg_val;
> + int ret;
> +
> + chip = container_of(gc, struct pca9539_chip, gpio_chip);
> +
> + if (val)
> + reg_val = chip->reg_output | (1u << off);
> + else
> + reg_val = chip->reg_output & ~(1u << off);
> +
> + ret = pca9539_write_reg(chip, PCA9539_OUTPUT, reg_val);
> + if (ret)
> + return;
> +
> + chip->reg_output = reg_val;
> +}
> +
> +static int pca9539_init_gpio(struct pca9539_chip *chip)
> +{
> + struct gpio_chip *gc;
> +
> + gc = &chip->gpio_chip;
> +
> + gc->direction_input = pca9539_gpio_direction_input;
Doubled space.
> + gc->direction_output = pca9539_gpio_direction_output;
> + gc->get = pca9539_gpio_get_value;
> + gc->set = pca9539_gpio_set_value;
> +
> + gc->base = chip->gpio_start;
> + gc->ngpio = NR_PCA9539_GPIOS;
> +
> + return gpiochip_add(gc);
> +}
> +
> +#ifndef MODULE
> +/* FIXME: change to schedule_delayed_work() here if reading out of
> + * registers does not reflect the actual pin levels
> + */
> +
> +static void pca9539_irq_work(struct work_struct *work)
> +{
> + struct pca9539_chip *chip;
> + uint16_t input, mask, rising, falling;
> + int ret, i;
> +
> + chip = container_of(work, struct pca9539_chip, irq_work);
>
> - if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
> - goto exit;
> + ret = pca9539_read_reg(chip, PCA9539_INPUT, &input);
> + if (ret < 0)
> + return;
>
> - /* OK. For now, we presume we have a valid client. We now create the
> - client structure, even though we cannot fill it completely yet. */
> - if (!(data = kzalloc(sizeof(struct pca9539_data), GFP_KERNEL))) {
> - err = -ENOMEM;
> - goto exit;
> + mask = (input ^ chip->last_input) & chip->irq_mask;
> + rising = (input & mask) & chip->irq_rising_edge;
> + falling = (~input & mask) & chip->irq_falling_edge;
> +
> + irq_enter();
> +
> + for (i = 0; i < NR_PCA9539_GPIOS; i++) {
> + if ((rising | falling) & (1u << i)) {
> + int irq = chip->irq_start + i;
> + struct irq_desc *desc;
> +
> + desc = irq_desc + irq;
> + desc_handle_irq(irq, desc);
> + }
> }
>
> - new_client = &data->client;
> - i2c_set_clientdata(new_client, data);
> - new_client->addr = address;
> - new_client->adapter = adapter;
> - new_client->driver = &pca9539_driver;
> - new_client->flags = 0;
> -
> - if (kind < 0) {
> - /* Detection: the pca9539 only has 8 registers (0-7).
> - A read of 7 should succeed, but a read of 8 should fail. */
> - if ((i2c_smbus_read_byte_data(new_client, 7) < 0) ||
> - (i2c_smbus_read_byte_data(new_client, 8) >= 0))
> - goto exit_kfree;
> + irq_exit();
> +
> + chip->last_input = input;
> +}
> +
> +static void fastcall
> +pca9539_irq_demux(unsigned int irq, struct irq_desc *desc)
> +{
> + struct pca9539_chip *chip = desc->handler_data;
> +
> + desc->chip->mask(chip->irq);
> + desc->chip->ack(chip->irq);
> + schedule_work(&chip->irq_work);
> + desc->chip->unmask(chip->irq);
> +}
> +
> +static void pca9539_irq_mask(unsigned int irq)
> +{
> + struct irq_desc *desc = irq_desc + irq;
> + struct pca9539_chip *chip = desc->chip_data;
> +
> + chip->irq_mask &= ~(1u << (irq - chip->irq_start));
> +}
> +
> +static void pca9539_irq_unmask(unsigned int irq)
> +{
> + struct irq_desc *desc = irq_desc + irq;
> + struct pca9539_chip *chip = desc->chip_data;
> +
> + chip->irq_mask |= 1u << (irq - chip->irq_start);
> +}
> +
> +static void pca9539_irq_ack(unsigned int irq)
> +{
> + /* unfortunately, we have to provide an empty irq_chip.ack even
> + * if we do nothing here, Generic IRQ will complain otherwise
> + */
> +}
> +
> +static int pca9539_irq_set_type(unsigned int irq, unsigned int type)
> +{
> + struct irq_desc *desc = irq_desc + irq;
> + struct pca9539_chip *chip = desc->chip_data;
> + uint16_t mask = 1u << (irq - chip->irq_start);
> +
> + if (type == IRQT_PROBE) {
> + if ((mask & chip->irq_rising_edge) ||
> + (mask & chip->irq_falling_edge) ||
> + (mask & ~chip->reg_direction))
> + return 0;
> +
> + type = __IRQT_RISEDGE | __IRQT_FALEDGE;
> }
>
> - strlcpy(new_client->name, "pca9539", I2C_NAME_SIZE);
> + gpio_direction_input(irq_to_gpio(irq));
>
> - /* Tell the I2C layer a new client has arrived */
> - if ((err = i2c_attach_client(new_client)))
> - goto exit_kfree;
> + if (type & __IRQT_RISEDGE)
> + chip->irq_rising_edge |= mask;
> + else
> + chip->irq_rising_edge &= ~mask;
>
> - /* Register sysfs hooks */
> - err = sysfs_create_group(&new_client->dev.kobj,
> - &pca9539_defattr_group);
> - if (err)
> - goto exit_detach;
> + if (type & __IRQT_FALEDGE)
> + chip->irq_falling_edge |= mask;
> + else
> + chip->irq_falling_edge &= ~mask;
>
> return 0;
> +}
>
> -exit_detach:
> - i2c_detach_client(new_client);
> -exit_kfree:
> - kfree(data);
> -exit:
> - return err;
> +static int pca9539_init_irq(struct pca9539_chip *chip)
> +{
> + struct irq_chip *ic = &chip->irq_chip;
> + int irq, irq_start = chip->irq_start;
> +
> + /* do not install GPIO interrupts for the chip if
> + * 1. the PCA9539 interrupt line is not used
> + * 2. or the GPIO interrupt number exceeds NR_IRQS
> + */
> + if (chip->irq <= 0 || irq_start + NR_PCA9539_GPIOS >= NR_IRQS)
> + return -EINVAL;
> +
> + chip->irq_mask = 0;
Doubled space.
> + chip->irq_rising_edge = 0;
Doubled space.
> + chip->irq_falling_edge = 0;
> +
> + ic->ack = pca9539_irq_ack;
> + ic->mask = pca9539_irq_mask;
> + ic->unmask = pca9539_irq_unmask;
> + ic->set_type = pca9539_irq_set_type;
> +
> + for (irq = irq_start; irq < irq_start + NR_PCA9539_GPIOS; irq++) {
> + set_irq_chip(irq, ic);
> + set_irq_chip_data(irq, chip);
> + set_irq_handler(irq, handle_edge_irq);
> + set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
> + }
> +
> + set_irq_type(chip->irq, IRQT_FALLING);
> + set_irq_data(chip->irq, chip);
> + set_irq_chained_handler(chip->irq, pca9539_irq_demux);
> +
> + INIT_WORK(&chip->irq_work, pca9539_irq_work);
> + return 0;
> }
> +#else
> +static inline int pca9539_init_irq(struct pca9539_chip *chip)
> +{
> + return 0;
> +}
> +#endif /* !CONFIG_MODULE */
>
> -static int pca9539_detach_client(struct i2c_client *client)
> +static int __devinit pca9539_probe(struct i2c_client *client)
> {
> - int err;
> + struct pca9539_platform_data *pdata;
> + struct pca9539_chip *chip;
> + int ret;
> +
> + pdata = client->dev.platform_data;
> + if (pdata == NULL)
> + return -ENODEV;
> +
> + chip = kzalloc(sizeof(struct pca9539_chip), GFP_KERNEL);
> + if (chip == NULL)
> + return -ENOMEM;
> +
> + chip->client = client;
> + chip->irq = client->irq;
>
> - sysfs_remove_group(&client->dev.kobj, &pca9539_defattr_group);
> + chip->gpio_start = pdata->gpio_base;
> + chip->irq_start = gpio_to_irq(chip->gpio_start);
Doubled space.
>
> - if ((err = i2c_detach_client(client)))
> - return err;
> + /* read init register values */
> + ret = pca9539_read_reg(chip, PCA9539_INPUT, &chip->last_input);
> + if (ret)
> + goto out_failed;
>
> - kfree(i2c_get_clientdata(client));
> + /* initialize registers */
> + chip->reg_output = 0xffff;
> + chip->reg_direction = 0xffff;
> +
> + pca9539_write_reg(chip, PCA9539_OUTPUT, chip->reg_output);
> + pca9539_write_reg(chip, PCA9539_DIRECTION, chip->reg_direction);
> +
> + /* set platform specific polarity inversion */
> + pca9539_write_reg(chip, PCA9539_INVERT, pdata->invert);
> +
> + ret = pca9539_init_gpio(chip);
> + if (ret)
> + goto out_failed;
> +
> + ret = pca9539_init_irq(chip);
> + if (ret)
> + goto out_failed;
> +
> + i2c_set_clientdata(client, chip);
> return 0;
> +
> +out_failed:
> + kfree(chip);
> + return ret;
> }
>
> +/* FIXME: PCA9539 is not supposed to be removed for now */
> +static struct i2c_driver pca9539_driver = {
> + .driver = {
> + .name = "pca9539",
> + },
> + .probe = pca9539_probe,
> +};
> +
> static int __init pca9539_init(void)
> {
> return i2c_add_driver(&pca9539_driver);
> @@ -193,4 +392,3 @@ MODULE_LICENSE("GPL");
>
> module_init(pca9539_init);
> module_exit(pca9539_exit);
> -
This whitespace cleanup doesn't really belong to this patch.
> diff --git a/include/linux/pca9539.h b/include/linux/pca9539.h
> new file mode 100644
> index 0000000..611d84a
> --- /dev/null
> +++ b/include/linux/pca9539.h
> @@ -0,0 +1,18 @@
> +/* platform data for the PCA9539 16-bit I/O expander driver */
> +
> +struct pca9539_platform_data {
> + /* number of the first GPIO */
> + unsigned gpio_base;
> +
> + /* initial polarity inversion setting */
> + uint16_t invert;
> +
> + void *context; /* param to setup/teardown */
> +
> + int (*setup)(struct i2c_client *client,
> + unsigned gpio, unsigned ngpio,
> + void *context);
> + int (*teardown)(struct i2c_client *client,
> + unsigned gpio, unsigned ngpio,
> + void *context);
> +};
Other than that I am fine with your patch:
Acked-by: Jean Delvare <khali at linux-fr.org>
I can't take your patch in my i2c tree as it depends on patches that
aren't upstream yet. It's probably easier to let David take care of it.
--
Jean Delvare
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