linux-kernel - Re: [PATCH v3 1/3] spi: spi-mem: add automatic poll status functions

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <865b01c8-12ff-cce6-557f-178effbc39a4@foss.st.com>
Date:   Tue, 18 May 2021 13:54:26 +0200
From:   Patrice CHOTARD <patrice.chotard@...s.st.com>
To:     Boris Brezillon <boris.brezillon@...labora.com>
CC:     Mark Brown <broonie@...nel.org>,
        Miquel Raynal <miquel.raynal@...tlin.com>,
        Vignesh Raghavendra <vigneshr@...com>,
        Alexandre Torgue <alexandre.torgue@...s.st.com>,
        <linux-spi@...r.kernel.org>,
        <linux-stm32@...md-mailman.stormreply.com>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>, <christophe.kerello@...s.st.com>
Subject: Re: [PATCH v3 1/3] spi: spi-mem: add automatic poll status functions



On 5/18/21 1:40 PM, Boris Brezillon wrote:
> On Tue, 18 May 2021 11:39:49 +0200
> <patrice.chotard@...s.st.com> wrote:
> 
>> +/**
>> + * spi_mem_poll_status() - Poll memory device status
>> + * @mem: SPI memory device
>> + * @op: the memory operation to execute
>> + * @mask: status bitmask to ckeck
>> + * @match: (status & mask) expected value
>> + * @initial_delay_us: delay in us before starting to poll
>> + * @polling_delay_us: time to sleep between reads in us
>> + * @timeout_ms: timeout in milliseconds
>> + *
>> + * This function send a polling status request to the controller driver
>> + *
>> + * Return: 0 in case of success, -ETIMEDOUT in case of error,
>> + *         -EOPNOTSUPP if not supported.
>> + */
>> +int spi_mem_poll_status(struct spi_mem *mem,
>> +			const struct spi_mem_op *op,
>> +			u16 mask, u16 match,
>> +			unsigned long initial_delay_us,
>> +			unsigned long polling_delay_us,
>> +			u16 timeout_ms)
>> +{
>> +	struct spi_controller *ctlr = mem->spi->controller;
>> +	int ret = -EOPNOTSUPP;
>> +	int read_status_ret;
>> +	u16 status;
>> +
>> +	if (op->data.nbytes < 1 || op->data.nbytes > 2)
>> +		return -EINVAL;
> 
> We should also make sure this is a read operation.

Ok , i will add a check here

Thanks
Patrice
> 
>> +
>> +	if (ctlr->mem_ops && ctlr->mem_ops->poll_status) {
>> +		ret = spi_mem_access_start(mem);
>> +		if (ret)
>> +			return ret;
>> +
>> +		ret = ctlr->mem_ops->poll_status(mem, op, mask, match,
>> +						 initial_delay_us, polling_delay_us,
>> +						 timeout_ms);
>> +
>> +		spi_mem_access_end(mem);
>> +	}
>> +
>> +	if (ret == -EOPNOTSUPP) {
>> +		if (!spi_mem_supports_op(mem, op))
>> +			return ret;
>> +
>> +		if (initial_delay_us < 10)
>> +			udelay(initial_delay_us);
>> +		else
>> +			usleep_range((initial_delay_us >> 2) + 1,
>> +				     initial_delay_us);
>> +
>> +		ret = read_poll_timeout(spi_mem_read_status, read_status_ret,
>> +					(read_status_ret || ((status) & mask) == match),
>> +					polling_delay_us, timeout_ms * 1000, false, mem,
>> +					op, &status);
>> +		if (read_status_ret)
>> +			return read_status_ret;
>> +	}
>> +
>> +	return ret;
>> +}